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Background Extra virgin olive oil (EVOO), the main fat in the Mediterranean diet, is consumed both raw and cooked. During the cooking process, its major and minor fractions are transformed, degraded, and oxidized due to exposure to heat and oxygen. Scope and approach This review examines the effect of cooking on EVOO, including the modification of its fatty acids and minor compounds; the interaction between EVOO and food matrices; the migration of components from the oil to food and vice versa; and how EVOO may enhance the stability and health properties of the cooked food. Key findings and conclusions EVOO has several advantages over other vegetable oils used in cooking. Its fatty acid profile and minor constituents keep the oil stable under high temperatures. By absorbing the oil, the cooked food is likewise protected from oxidation and enriched with EVOO health-promoting bioactive compounds. Finally, food bioactive compounds become more bioavailable upon migration to the oil.

The objective is to verify if gluten-free (GF) and gluten-containing (G) breads differ in their sodium content and lipid profile. Samples of GF (n = 20) and G (n = 14) sliced white sandwich bread of commercial brands most frequently consumed in Spain were collected. The fatty acid (FA) composition and the contents of sodium, fat, cholesterol and phytosterols were determined. Sodium, fat and cholesterol contents were significantly higher in GF bread. The FA composition also differed, while G breads declared in most instances the use of sunflower oil as fat ingredient and presented a higher polyunsaturated FA percentage; GF breads declared a wide variety of fats and oils as ingredients (coconut, palm, olive, sunflower, etc.) which was reflected in their FA profile. Cholesterol content was higher in GF bread because five samples declared the use of whole egg, while G samples did not include any egg product in their formulas. Phytosterol content was higher in G bread but its variability was greater in GF bread. In conclusion, nutritional quality of GF bread varied depending on the ingredients used and might be lower than that of G bread. However, these differences in composition could be reduced or eliminated through changes in the formulation of GF bread. Moreover, the comparison of the results obtained in our laboratory for fat and salt content with the declared contents on the labels showed a much higher deviation for GF samples and it can be concluded that the quality of the nutritional information declared was lower in GF samples. Electronic supplementary material The online version of this article (10.1007/s11130-020-00828-w) contains supplementary material, which is available to authorized users.

According to the last report from the European Union (EU) Food Fraud Network, olive oil tops the list of the most notified products. Current EU regulation states geographical origin as mandatory for virgin olive oils, even though an official analytical method is still lacking. Verifying the compliance of label-declared EU oils should be addressed with the highest priority level. Hence, the present work tackles this issue by developing a classification model (PLS-DA) based on the sesquiterpene hydrocarbon fingerprint of 400 samples obtained by HS-SPME-GC-MS to discriminate between EU and non-EU olive oils, obtaining an 89.6% of correct classification for the external validation (three iterations), with a sensitivity of 0.81 and a specificity of 0.95. Subsequently, multi-class discrimination models for EU and non-EU countries were developed and externally validated (with three different validation sets) with successful results (average of 92.2% of correct classification for EU and 96.0% for non-EU countries). Keywords: Authenticity; Fingerprint; Geographical origin; PLS-DA; SPME-GC-MS; Sesquiterpene hydrocarbons; Virgin Olive Oil.

[spa] La industria vitivinícola genera una gran cantidad de subproductos. Entre ellos el subproducto más abundante son los sarmientos de vid originados durante la temporada de poda. Los sarmientos de vid poseen una mezcla compleja de compuestos fenólicos los que incluyen ácidos fenólicos, flavonoides, y estilbenos, que a su vez están asociados con una amplia gama de beneficios para la salud. El perfil fenólico de los sarmientos es altamente dependiente del tipo de cultivar, la zona geográfica de cultivo, y de las condiciones de almacenamiento posteriores a la poda. Los procesos y sistemas de extracción también influyen fuertemente en el perfil de los compuestos fenólicos. Aunque existen numerosos estudios de recuperación e identificación de compuestos fenólicos obtenidos desde sarmientos de vid, muy pocos de ellos se han centrado en el estudio del escalamiento de los procesos de extracción y en el efecto sobre el perfil fenólico. Por otro lado, los compuestos fenólicos son reconocidos por ser inestables y sensibles a altas temperaturas, la luz, el pH y las enzimas oxidativas y degradantes. Estas variables afectan al perfil fenólico tanto en los procesos de producción como en la estabilidad de los productos finales. Una opción viable a escala industrial que permite solucionar estos problemas es la encapsulación de estos compuestos en ciclodextrinas, que les proporcionan una matriz protectora y les ayuda a preservar sus actividades biológicas. Por todas estas razones, esta tesis tiene por objetivo estudiar los cambios en el perfil fenólico de un extracto de sarmientos durante su producción y encapsulación, mediante cromatografía de líquidos acoplada a espectrometría de masas de alta resolución. La espectrometría de masas de alta resolución basada en LC-ESI-LTQ-Orbitrap-MS ha demostrado ser una poderosa herramienta de identificación y caracterización de compuestos fenólicos. El uso de este equipo nos permitió identificar nuevos compuestos en los extractos de sarmientos de vid producidos a escala de laboratorio. También fue útil para estudiar los cambios en el perfil fenólico durante la extracción a escala piloto y posterior encapsulación de estos compuestos en ciclodextrinas. Los resultados de esta tesis doctoral permitieron ampliar el conocimiento del perfil fenólico de los extractos de sarmientos de vid, analizar las diferencias de los extractos desde la extracción de laboratorio, a la extracción piloto hasta su posterior encapsulación en ciclodextrinas, permitiendo el desarrollo de un producto de alto valor agregado y con futuras aplicaciones en las industrias alimentaria y farmacéutica., [eng] The wine industry produces many by-products. The most common by-product is the grape canes (or vine shoots) that are produced during the pruning season. Grape canes contain a complex mixture of phenolic compounds, including phenolic acids, flavonoids, and stilbenes, which in turn have been linked to several health benefits. The phenolic profile of grape canes is highly dependent on the variety, the geographical area of cultivation, and the storage conditions after pruning. Extraction methods and systems also strongly influence the profile of phenolic compounds. Although there are numerous studies on the extraction and identification of phenolic compounds from grape canes, very few of them have focused on the study of the scaling-up of the extraction process and the effects on the phenolic profile. On the other hand, phenolic compounds are known to be unstable and sensitive to high temperature, light, pH, and oxidative and degradative enzymes. These variables affect the phenolic profile both in the production processes and in the stability of the final products. A viable way to address these issues on an industrial scale is to encapsulate these compounds in cyclodextrins, which allows them to obtain a protective matrix and retain their biological activities. For all these reasons, this PhD aims to study the changes in the phenolic profile of a grape cane extract during its production and encapsulation using liquid chromatography coupled with high-resolution mass spectrometry. High-resolution mass spectrometry-based on LC-ESI-LTQ-Orbitrap-MS has proven to be a powerful tool for the identification and characterization of phenolic compounds. The use of this equipment allowed us to identify new compounds in extracts of grape canes. It was also useful to study the changes in phenolic profile during pilot-scale extraction and subsequent encapsulation of these compounds in cyclodextrins. The results of this PhD allowed to increase the knowledge of the phenolic profile of extracts from grape canes, to analyze the differences of the extracts from laboratory extraction to pilot extraction and their encapsulation in cyclodextrins, leading to the development of a product with high added value and with future applications in the food and pharmaceutical industries.

Gas chromatography—ion mobility spectrometry (GC-IMS) allows the fast, reliable, and inexpensive chemical composition analysis of volatile mixtures. This sensing technology has been successfully employed in food science to determine food origin, freshness and preventing alimentary fraud. However, GC-IMS data is highly dimensional, complex, and suffers from strong non-linearities, baseline problems, misalignments, peak overlaps, long peak tails, etc., all of which must be corrected to properly extract the relevant features from samples. In this work, a pipeline for signal pre-processing, followed by four different approaches for feature extraction in GC-IMS data, is presented. More precisely, these approaches consist of extracting data features from: (1) the total area of the reactant ion peak chromatogram (RIC), (2) the full RIC response, (3) the unfolded sample matrix, and (4) the ion peak volumes. The resulting pipelines for data processing were applied to a dataset consisting of two different quality class Iberian ham samples, based on their feeding regime. The ability to infer chemical information from samples was tested by comparing the classification results obtained from partial least-squares discriminant analysis (PLS-DA) and the samples’ variable importance for projection (VIP) scores. The choice of a feature extraction strategy is a trade-off between the amount of chemical information that is preserved, and the computational effort required to generate the data models.

Nowadays, 144 Protected Designations of Origin (PDO) and Protected Geographical Indications (PGI) under the EU quality schemes correspond to extra virgin olive oil (EVOO). As endorsed by the EU Food Fraud Network, PDO/PGI EVOOs are particularly vulnerable to fraudulent practices because of their high economic value. For this reason, the present study aims to develop an instrumental tool to assess the compliance of EVOO with PDO label-declaration using a large sample set (n = 350). As a case study, PDOs from Catalonia were used. Therefore, discriminant analysis based on the sesquiterpene hydrocarbon fingerprint determined by HS-SPME-GC-MS achieved to correctly classify an average of 93.6% of samples among the four Catalan PDOs, leaving unassigned the 6% of the total sampling (external validation results for 3 iterations). On the other hand, the proposed strategy allowed discriminating each Catalan PDO from non-PDO samples produced in different geographical areas with an efficiency between 95% and 99%. info:eu-repo/semantics/publishedVersion

Virgin olive oil (VOO) is a highly appreciated product fundamental in the Mediterranean diet. Since its sensory attributes are greatly influenced by the olive cultivar, the varietal authentication of VOOs is needed to protect consumers from misleading information. The present study aims to evaluate the suitability of sesquiterpene hydrocarbon (SH) fingerprint as VOO cultivar marker beyond geographical, agronomical and processing con ditions. The study was mainly focused on Mediterranean Arbequina oils. SH profile of more than 400 VOOs from 6 counties and 38 different cultivars and coupages was analysed by Headspace Solid Phase Microextraction-Gas Chromatography-Mass Spectrometry (HS-SPME-GC-MS). Partial Least Square-Discriminant Analysis (PLS-DA) classification models were built with the aligned chromatograms. A binary PLS-DA model was built to distinguish ‘Arbequina’ oils from those of other cultivars (non-‘Arbequina’ class) and it was externally validated. The results of the external validation showed a 95.1% of overall correct classification confirming the suitability of SH fingerprint as a screening method for the authentication of Arbequina VOO. Also, the discrimination capacity of SH fingerprinting to authenticate VOOs from other cultivars was preliminary explored and promising results were obtained. info:eu-repo/semantics/publishedVersion

[spa] La industria vitivinícola genera una gran cantidad de subproductos. Entre ellos el subproducto más abundante son los sarmientos de vid originados durante la temporada de poda. Los sarmientos de vid poseen una mezcla compleja de compuestos fenólicos los que incluyen ácidos fenólicos, flavonoides, y estilbenos, que a su vez están asociados con una amplia gama de beneficios para la salud. El perfil fenólico de los sarmientos es altamente dependiente del tipo de cultivar, la zona geográfica de cultivo, y de las condiciones de almacenamiento posteriores a la poda. Los procesos y sistemas de extracción también influyen fuertemente en el perfil de los compuestos fenólicos. Aunque existen numerosos estudios de recuperación e identificación de compuestos fenólicos obtenidos desde sarmientos de vid, muy pocos de ellos se han centrado en el estudio del escalamiento de los procesos de extracción y en el efecto sobre el perfil fenólico. Por otro lado, los compuestos fenólicos son reconocidos por ser inestables y sensibles a altas temperaturas, la luz, el pH y las enzimas oxidativas y degradantes. Estas variables afectan al perfil fenólico tanto en los procesos de producción como en la estabilidad de los productos finales. Una opción viable a escala industrial que permite solucionar estos problemas es la encapsulación de estos compuestos en ciclodextrinas, que les proporcionan una matriz protectora y les ayuda a preservar sus actividades biológicas. Por todas estas razones, esta tesis tiene por objetivo estudiar los cambios en el perfil fenólico de un extracto de sarmientos durante su producción y encapsulación, mediante cromatografía de líquidos acoplada a espectrometría de masas de alta resolución. La espectrometría de masas de alta resolución basada en LC-ESI-LTQ-Orbitrap-MS ha demostrado ser una poderosa herramienta de identificación y caracterización de compuestos fenólicos. El uso de este equipo nos permitió identificar nuevos compuestos en los extractos de sarmientos de vid producidos a escala de laboratorio. También fue útil para estudiar los cambios en el perfil fenólico durante la extracción a escala piloto y posterior encapsulación de estos compuestos en ciclodextrinas. Los resultados de esta tesis doctoral permitieron ampliar el conocimiento del perfil fenólico de los extractos de sarmientos de vid, analizar las diferencias de los extractos desde la extracción de laboratorio, a la extracción piloto hasta su posterior encapsulación en ciclodextrinas, permitiendo el desarrollo de un producto de alto valor agregado y con futuras aplicaciones en las industrias alimentaria y farmacéutica. [eng] The wine industry produces many by-products. The most common by-product is the grape canes (or vine shoots) that are produced during the pruning season. Grape canes contain a complex mixture of phenolic compounds, including phenolic acids, flavonoids, and stilbenes, which in turn have been linked to several health benefits. The phenolic profile of grape canes is highly dependent on the variety, the geographical area of cultivation, and the storage conditions after pruning. Extraction methods and systems also strongly influence the profile of phenolic compounds. Although there are numerous studies on the extraction and identification of phenolic compounds from grape canes, very few of them have focused on the study of the scaling-up of the extraction process and the effects on the phenolic profile. On the other hand, phenolic compounds are known to be unstable and sensitive to high temperature, light, pH, and oxidative and degradative enzymes. These variables affect the phenolic profile both in the production processes and in the stability of the final products. A viable way to address these issues on an industrial scale is to encapsulate these compounds in cyclodextrins, which allows them to obtain a protective matrix and retain their biological activities. For all these reasons, this PhD aims to study the changes in the phenolic profile of a grape cane extract during its production and encapsulation using liquid chromatography coupled with high-resolution mass spectrometry. High-resolution mass spectrometry-based on LC-ESI-LTQ-Orbitrap-MS has proven to be a powerful tool for the identification and characterization of phenolic compounds. The use of this equipment allowed us to identify new compounds in extracts of grape canes. It was also useful to study the changes in phenolic profile during pilot-scale extraction and subsequent encapsulation of these compounds in cyclodextrins. The results of this PhD allowed to increase the knowledge of the phenolic profile of extracts from grape canes, to analyze the differences of the extracts from laboratory extraction to pilot extraction and their encapsulation in cyclodextrins, leading to the development of a product with high added value and with future applications in the food and pharmaceutical industries.

Highlights • All the analytical methods have been successfully applied to acid oils and fatty acid distillates. • A detailed description of the sample preparation for analysis and applied analytical methods is provided as a compendium of methods in the supplementary material. • These methods will be extremely useful to improve the quality control of these heterogeneous feed ingredients., Acid oils and fatty acid distillates are by-products from the refining of edible oils and fats. They are used as feed ingredients, but their highly variable composition sometimes affects the productive parameters of the animals. Thus, their quality control and standardization are necessary. The official methods recommended for crude and refined fats and oils must be modified to give reliable results when applied to acid oils and fatty acid distillates. This article summarizes the drawbacks that were encountered during the setup of the analytical methods and how were they overcome by adapting the methods to these type of fat samples. Some methods such as the determinations of fatty acid composition, tocopherol and tocotrienol content, unsaponifiable matter, acidity and peroxide value had to be minimally adapted. However, others such as the determinations of moisture and volatile matter, insoluble impurities, lipid classes and p-anisidine value showed important drawbacks that required a more significant adaptation.•All the analytical methods have been successfully applied to acid oils and fatty acid distillates.•A detailed description of the sample preparation for analysis and applied analytical methods is provided as a compendium of methods in the supplementary material.•These methods will be extremely useful to improve the quality control of these heterogeneous feed ingredients., Graphical abstract Image, graphical abstract

Treballs Finals de Grau de Nutrició Humana i Dietètica, Facultat de Farmàcia i Ciències de l'Alimentació, Campus de l'Alimentació de Torribera, Universitat de Barcelona. Curs: 2020-2021. Tutor: Alba Tres Oliver, [cat] El consum d’algues s’ha incrementat durant aquests últims anys. Aquestes es poden classificar per la seva grandària en micro i macroalgues. Però, quin és el valor nutricional d’aquestes? Són segures per al consumidor? Per contestar aquestes preguntes aquest article de revisió ha estat basat principalment en articles científics recents cercats a diferents bases com PubMed o Scopus. Tant les microalgues com les macroalgues es componen majoritàriament de carbohidrats, seguit de proteïnes, lípids, minerals i vitamines. En general destaquen pel seu contingut en polisacàrids complexos, àcids grassos poliinsaturats com EPA i DHA, una composició d’aminoàcids similar a la de l’ou i la soja, múltiples vitamines, com ara provitamines A i B12 i minerals entre ells sodi, potassi, ferro i iode. Aquesta composició nutricional és la que les ha posat en valor al mercat, com a suplements d’EPA, DHA o vitamina B12. També pels seus beneficis com antioxidants, propietats antivirals, anticancerígenes i anticoagulants, entre altres. Ara bé, cal tenir en compte la possible acumulació de tòxics, com metalls pesants, plaguicides o un excés de iode que es podria produir pel seu consum., [eng] The consumption of seaweed has increased in recent years. They can be classified according to their size into micro and macroalgae. But what is the nutritional value of these? Are they safe for the consumer? In order to answer these questions, this review article has been based mainly on recent scientific articles searched in different databases such as PubMed or Scopus. Both microalgae and macroalgae are mainly composed of carbohydrates, followed by proteins, lipids, minerals, and vitamins. In general, they are notable for their content of complex polysaccharides, polyunsaturated fatty acids such as EPA and DHA, an amino acid composition similar to eggs and soya, multiple vitamins, such as pro-vitamin A and B12, and minerals including sodium, potassium, iron and iodine. It is this nutritional composition that has placed them on the market as supplements for EPA, DHA and vitamin B12. Also, for their benefits as antioxidants, antiviral, anticancer and anticoagulant properties, among others. However, it is important to consider the possible accumulation of toxins, such as heavy metals, pesticides or an excess of iodine that could be produced by its consumption.

Quinoa (Chenopodium quinoa Willd.) is an andean grain with exceptional nutritional properties that has been progressively introduced in western countries as a protein-rich super food with a broad amino acid spectrum. Quinoa is consumed as whole grain, but it is also milled to produce high-value flour, which is susceptible to adulteration. Therefore, there is a growing interest in developing novel analytical methods to get further information about quinoa at the chemical level. In this study, we developed a rapid and simple capillary electrophoresis-ultraviolet absorption diode array detection (CE-UV-DAD) method to obtain characteristic multiwavelength electrophoretic profiles of soluble protein extracts from different quinoa grain varieties. Then, advanced chemometric methods (i.e. multivariate curve resolution alternating least squares, MCR-ALS, followed by principal component analysis, PCA, and partial least squares discriminant analysis, PLS-DA) were applied to deconvolute the components present in the electropherograms and classify the quinoa varieties according to their differential protein composition.

In this study, the feasibility of non-targeted UHPLC-HRMS fingerprints as chemical descriptors to address the classification and authentication of paprika samples was evaluated. Non-targeted UHPLC-HRMS fingerprints were obtained after a simple sample extraction method and C18 reversed-phase separation. Fingerprinting data based on signal intensities as a function of m/z values and retention times were registered in negative ion mode using a q-Orbitrap high-resolution mass analyzer, and the obtained non-targeted UHPLC-HRMS fingerprints subjected to unsupervised principal component analysis (PCA) and supervised partial least squares regression-discriminant analysis (PLS-DA) to study sample discrimination and classification. A total of 105 paprika samples produced in three different regions, La Vera PDO and Murcia PDO, in Spain, and the Czech Republic, and all of them composed of samples of at least two different taste varieties, were analyzed. Non-targeted UHPLC-HRMS fingerprints demonstrated to be excellent sample chemical descriptors to achieve the authentication of paprika production regions with 100% sample classification rates by PLS-DA. Besides, the obtained fingerprints were also able to perfectly discriminate among the different paprika taste varieties in all the studied cases, even in the case of the different La Vera PDO paprika tastes (sweet, bittersweet, and spicy) which are produced in a very small region.

61 Páginas.-- 5 Tablas.-- 1 Figura, 1H NMR fingerprinting of edible oils and a set of multivariate classification and regression models organised in a decision tree is proposed as a stepwise strategy to assure the authenticity and traceability of olive oils and their declared blends with other vegetable oils (VOs). Oils of the 'virgin olive oil' and 'olive oil' categories and their mixtures with the most common VOs, i.e. sunflower, high oleic sunflower, hazelnut, avocado, soybean, corn, refined palm olein and desterolized high oleic sunflower oils, were studied. Partial least squares (PLS) discriminant analysis provided stable and robust binary classification models to identify the olive oil type and the VO in the blend. PLS regression afforded models with excellent precisions and acceptable accuracies to determine the percentage of VO in the mixture. The satisfactory performance of this approach, tested with blind samples, confirm its potential to support regulations and control bodies., This work was developed in the framework of the project OLEUM “Advanced solutions for assuring authenticity and quality of olive oil at global scale” funded by the European Commission within the Horizon 2020 Programme (2014–2020), grant agreement No. 635690; and the project AUTENFOOD funded by ACCIÓ-Generalitat de Catalunya and the European Union through the Programa Operatiu FEDER Catalunya 2014-2020 (Ref COMRDI-15-1-0035). The information contained in this article reflects the authors’ views; the European Commission is not liable for any use of the information contained herein. The authors would like to thank all producers that supplied the olive oils, virgin olive oils and vegetable oils for this study, and the technical and staff support provided by SGIker (UPV/EHU, MICINN, GV/EJ, ESF).

The socioeconomic, cultural, therapeutic, and nutritional potential of Amazonian fruits has been limited due to the scarce information about its phytochemical profile. The aim of this study was to determine the total phenolic content profiles by Folin colorimetric miniaturized assay, the identification of phenolic compounds by UHPLC-HRMS, the antioxidant capacity by DPPH, ABTS, and NBT assays, as well as, the antiproliferative activity by sulforhodamine B assay of extracts obtained from ten native fruits to the Amazon region, some of these consumed especially by indigenous population. A strong positive correlation between the content of total phenolic compounds and antioxidant capacity was demonstrated. The antiproliferative activities against Caco-2 cell line didn't necessarily be associated with a high antioxidant capacity and the total phenolic concentration, possibly, qualitative and quantitative differences in phenolic composition of these fruits influenced the antiproliferative activities. This research presented, for the first time, important characteristics of Amazon exotic fruits.

Food products are very complex mixtures consisting of naturally-occurring compounds and other substances, generally originating from technological processes, agrochemical treatments, or packaging materials. Several of these compounds (e.g., veterinary drugs, pesticides, mycotoxins, etc.) are of particular concern because, although they are generally present in very small amounts, they are nonetheless often dangerous to human health. On the other hand, food is no longer just a biological necessity for survival. Society, in general, demands healthy and safe food, but it is also increasingly interested in other quality attributes more related to the origin of the food, the agricultural production processes used, the presence or not of functional compounds, etc. In an increasingly populated world and with an increasingly demanding society regarding food quality, food production has become a completely global aspect on a global level. In addition, in this field, where the number of people involved in the food production process, from its origin to its consumption, is enormous, it is increasingly difficult to guarantee the integrity and, above all, the authenticity of foodstuffs. In consequence, improved methods for the determination of authenticity, standardization, and efficacy of nutritional properties in natural food products are required to guarantee their quality and for the growth and regulation of the market. Thus, food safety and food authentication are hot topics for both society and the food industry.

In the context of supporting the panel test in the classification of virgin olive oils, the qualitative and quantitative analysis of a number of volatile compounds responsible for their aroma is of great importance. Herein, the data obtained from three laboratories that analyzed the same samples are presented with the view to develop an inter-laboratory validation study of a harmonized solid-phase micro-extraction coupled with gas-chromatography with flame ionized detector (SPME-GC-FID) method for determination of selected volatile compounds. In particular, quantification of the minimum number of key markers responsible for positive attributes (e.g. fruity) and sensory defects was investigated. Three quantification strategies were considered since they can have a notable impact on the effectiveness of the use of markers as well as on the robustness and simplicity of the method that is designed for control laboratories. A peer-validation study indicated repeatability with a mean relative standard deviation (RSD%) lower than 14% except for ethyl propanoate, 3-methyl-1-butanol, 1-octen-3-ol, and (E)-2-decenal. Linearity was satisfactory (R2 > 0.90) for all compounds when the calibration curves were corrected by the internal standard. Several critical issues were identified, such as high RSD% (>50%) in terms of reproducibility for ethyl propanoate, (E)-2-decenal, and possible improvements of the limits of detection (LODs) and quantitation (LOQs) of (E)-2-heptenal, (E,E)-2,4-hexadienal, and (E)-2-decenal. In particular, some compounds (ethyl propanoate, (E)-2-heptenal, 1-octen-3-ol, (E,E)-2,4-hexadienal, (E)-2-decenal and pentanoic acid) showed LOQs that were higher than the concentrations found in some samples. The discussion permitted improvement of the protocol towards the final version for an upcoming full validation process., This work was supported by the Horizon 2020 European Research project OLEUM “Advanced solutions for assuring the authenticity and quality of olive oil at a global scale”, which has received funding from the European Commission within the Horizon 2020 Programme (2014–2020), grant agreement no. 635690. The information expressed in this article reflects the authors’ views; the European Commission is not liable for the information contained herein. B. Quintanilla-Casas and A. Tres thanks the Spanish Ministry of Science, Innovation and Universities for a predoctoral (FPU16/01744) and a Ramón y Cajal (RYC-2017-23601) postdoctoral fellowship, respectively.

TFG Premi Càtedra UB-DANONE 2020. Universitat de Barcelona, Facultat de Farmàcia i Ciències de l'Alimentació, Campus de l'Alimentació de Torribera / DANONE. Tutor: Rosa M. Lamuela Raventós, Treball Final de Grau de Ciència i Tecnologia dels Aliments, Facultat de Farmàcia i Ciències de l'Alimentació, Campus de l'alimentació de Torribera, Universitat de Barcelona. Curs: 2019-2020. Tutor: Rosa Ma. Lamuela Raventós, [eng] Extra virgin olive oil (EVOO) contains polyphenols, which protect LDL cholesterol from oxidation. Its concentration depends on different agrological and technical factors, such as the ripening stage and the temperature of crushing. The aim of this study was to evaluate the impact of these two factors on the ‘Corbella’ EVOO phenolic profile. The polyphenols were measured at three degrees of ripeness (maturity index (IM) = 0.3; IM = 1.2; IM = 3.2) and three crushing temperatures (10 °C, 18 °C and 25 °C) in EVOO. These compounds were analysed by ultra-high-performance liquid chromatography coupled to a tandem mass spectrometer. The conclusions that could be reached after completing the work are that the sum of polyphenols decrease when the crushing temperature is increased, but individual polyphenols like oleocanthal or oleacein increase. Further, total polyphenols decrease with fruit maturity. Instead, flavones, hydroxyoleuropein aglycone, hydroxytyrosol acetate and lignans increase., [cat] L’oli d’oliva verge extra (OOVE) conté polifenols que protegeixen el colesterol LDL de l’oxidació. La seva concentració depèn de diferents factors agraris i tècnics, com ara l’estadi de maduració i la temperatura de trituració. L’objectiu d’aquest treball va ser avaluar l’impacte d’aquests dos factors en el perfil fenòlic de l’OOVE de “Corbella”. Els polifenols de l’OOVE es van mesurar a tres graus de maduració (índex de maduresa (IM) = 0,3; IM = 1,2; IM = 3,2) i tres temperatures de trituració (10 °C, 18 °C i 25 °C). Aquests compostos es van analitzar mitjançant cromatografia líquida d’alta eficàcia acoblada a un espectròmetre de masses en tàndem. Les conclusions a les que es podria arribar després de finalitzar el treball són que la suma de polifenols disminueix quan augmenta la temperatura de trituració, però augmenten polifenols individuals com l’oleocantal o l’oleaceïna. A més, els polifenols totals disminueixen amb la maduresa de la fruita. En canvi, augmenten les flavones, l’aglicona d’hidroxioleuropeïna, l’acetat d’hidroxitirosol i els lignans.

UHPLC-HRMS (Orbitrap) fingerprinting in negative and positive H-ESI mode was applied to the characterization, classification and authentication of cranberry-based natural and pharmaceutical products. HRMS data in full scan mode (m/z 100-1500) at a resolution of 70,000 full-width at half maximum was recorded and processed with MSConvert software to obtain a profile of peak intensities in function of m/z values and retention times. A threshold peak filter of absolute intensity (105 counts) was applied to reduce data complexity. Principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) revealed patterns able to discriminate the analyzed samples according to the fruit of origin (cranberry, grape, blueberry and raspberry). Discrimination among cranberry-based natural and cranberry-based pharmaceutical preparations was also achieved. Both, UHPLC-HRMS fingerprints in negative and positive H-ESI modes, as well as the data fusion of both acquisition modes, showed to be good chemical descriptors to address cranberry extracts authentication. Validation of the proposed methodology showed a prediction rate of 100% of the samples. Obtained data was further treated by partial least squares (PLS) regression to identify frauds and quantify the percentage of adulterant fruits in cranberry-fruit extracts, achieving prediction errors in the range 0.17-3.86%.

In this work, non-targeted ultra-high performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS) fingerprints obtained by C18 reversed-phase chromatography were proposed as sample chemical descriptors for the characterization and classification of turmeric and curry samples. A total of 21 turmeric and 9 curry commercially available samples were analyzed in triplicate after extraction with dimethyl sulfoxide (DMSO). The results demonstrated the feasibility of non-targeted UHPLC-HRMS fingerprints for sample classification, showing very good classification capabilities by partial least squares regression-discriminant analysis (PLS-DA), with 100% classification rates being obtained by PLS-DA when randomly selected samples were processed as &ldquo, unknown&rdquo, ones. Besides, turmeric curcuma species (Curcuma longa vs. Curcuma zedoaria) and turmeric Curcuma longa varieties (Madras, Erodes, and Alleppey) discrimination was also observed by PLS-DA when using the proposed fingerprints as chemical descriptors. As a conclusion, non-targeted UHPLC-HRMS fingerprinting is a suitable methodology for the characterization, classification, and authentication of turmeric and curry samples, without the requirement of using commercially available standards for quantification nor the necessity of metabolite identification.

TFG Premi Càtedra UB-DANONE 2019. Universitat de Barcelona, Facultat de Farmàcia i Ciències de l'Alimentació, Campus de l'Alimentació de Torribera / DANONE. Tutor: Francisco José Pérez Cano, Treball Final de Grau de Ciència i Tecnologia dels Aliments, Facultat de Farmàcia i Ciències de l'Alimentació, Campus de l'alimentació de Torribera, Universitat de Barcelona. Curs: 2018-2019. Tutor: Francisco J. Pérez-Cano, [spa] Estudios previos han mostrado los efectos del cacao o de sus componentes bioactivos aislados sobre la función inmunitaria y sobre la salud. En el presente artículo, se muestra la heterogeneidad en cuanto a polifenoles totales y el efecto inmunomodulador según el origen del cacao sobre leucocitos esplénicos, analizando la secreción de citocinas TNFα e IL-10. Los esplenocitos fueron extraídos del bazo de ratas Brown Norway mediante la disgregación de este y purificación de la suspensión celular. Dichas células fueron cultivadas y tratadas con 10 µg/mL de las diferentes variedades de cacao, lo cual no afectó a la proliferación celular, durante 2 horas y, posteriormente, estimuladas con 100 ng/mL de LPS durante toda la noche. Se observó que dos variedades de cacao (codificación: P07 y P09) conseguían una disminución de la secreción de IL-10, y otras dos variedades (codificación: P01 y P09) presentaban diferencias significativas entre ellas en la secreción de TNFα. Estos resultados revelan el efecto inmunomodulador diferencial según el origen del cacao., [eng] Previous studies have shown the effects of cocoa or its isolated bioactive components on immune function and health. This article shows the heterogeneity in terms of total polyphenols and the immunomodulatory effect according to the origin of cocoa on splenic leukocytes, analyzing the secretion of TNFα and IL-10 cytokines. Splenocytes were extracted from the spleen of Brown Norway rats by disintegrating it and purifying the cell suspension. These cells were cultured and treated with 10 µg / mL of the different cocoa varieties, which did not affect cell proliferation, for 2 hours and subsequently stimulated with 100 ng / mL of LPS overnight. It was observed that two cocoa varieties 2(coding: P07 and P09) achieved a decrease in the secretion of IL-10, and two other varieties (coding: P01 and P09) had significant differences between them in the secretion of TNFα. These results reveal the differential immunomodulatory effect depending on the origin of cocoa.

&Tau, oward a harmonized and standardized procedure for the determination of total hydroxytyrosol and tyrosol content in virgin olive oil (VOO), the pros of a recently published in house validated ultra high performance liquid chromatography (UHPLC) protocol are discussed comparatively with those of other procedures that determine directly or indirectly the compounds hosted under the health claim on &ldquo, olive oil polyphenols&rdquo, (EC regulation 432/2012). Authentic VOOs were analyzed with five different liquid chromatographic separation protocols and 1H-NMR one in five different laboratories with expertise in VOO phenol analysis within three months. Data comparison indicated differences in absolute values. Method comparison using appropriate tools (Passing-Bablok regression and Bland Altman analyses) for all protocols vs. the UHPLC one indicated slight or statistically significant differences. The results were also discussed in terms of cost effectiveness, detection means, standard requirements and ways to calculate the total hydroxytyrosol and tyrosol content. Findings point out that the in-house validated fit for the purpose UHPLC protocol presents certain pros that should be exploited by the interested parties. These are the simplicity of sample preparation, fast elution time that increase the number of samples analyzed per day and integration of well-resolved peaks with the aid of only two commercially available external standards. Importance of correction factors in the calculations is stressed.

The phenols and fatty acids profile and in vitro antioxidant and hypoglycaemic activity of seed, peel, pulp or pulp plus seeds of Colombian fruits from Solanaceae and Passifloraceae families were investigated. Ultra-High Performance Liquid Chromatography (UHPLC)-High Resolution Mass Spectrometry (HRMS) revealed the presence of chlorogenic acid as dominant phenolic compound in Solanaceae samples. Based on the Relative Antioxidant Score (RACI) and Global Antioxidant Score (GAS) values, Solanum quitoense peel showed the highest antioxidant potential among Solanaceae samples while Passiflora tripartita fruits exhibited the highest antioxidant effects among Passifloraceae samples. P. ligularis seeds were the most active as hypoglycaemic agent with IC50 values of 22.6 and 24.8 &mu, g/mL against &alpha, amylase and &alpha, glucosidase, respectively. Considering that some of the most promising results were obtained by the processing waste portion, its use as functional ingredients should be considered for the development of nutraceutical products intended for patients with disturbance of glucose metabolism.

An analytical method for determination of arsenic species (inorganic arsenic (iAs), methylarsonic acid (MA), dimethylarsinic acid (DMA), arsenobetaine (AB), trimethylarsine oxide (TMAO) and arsenocholine (AC)) in Brazilian and Spanish seafood samples is reported. This study was focused on extraction and quantification of inorganic arsenic (iAs), the most toxic form. Arsenic speciation was carried out via LC with both anionic and cationic exchange with ICP-MS detection (LC-ICP-MS). The detection limits (LODs), quantification limits (LOQs), precision and accuracy for arsenic species were established. The proposed method was evaluated using eight reference materials (RMs). Arsenobetaine was the main species found in all samples. The total and iAs concentration in 22 seafood samples and RMs ranged between 0.27–35.2 and 0.02–0.71 mg As kg−1, respectively. Recoveries ranging from 100% to 106% for iAs, based on spikes, were achieved. The proposed method provides reliable iAs data for future risk assessment analysis.

4 Tablas.-- 4 Figuras, The determination of the total hydroxytyrosol (Htyr) and tyrosol (Tyr) content of virgin olive oil is of utmost interest for the International Olive Council (IOC), food authorities, producers, and distributors after the issuing of a health claim that “olive oil polyphenols contribute to the protection of blood lipids from oxidative stress.” To address the need of a harmonized and standardized protocol the present study focuses on the extraction solvent of the polar fraction. Aqueous mixtures of methanol and acetonitrile of equal polarity are prepared and comparatively examined. Different analytical approaches (Folin-Ciocalteu assay, reversed phase chromatography-diode array-fluorescence detection, LC-Orbitrap, LC-TOF, LC-TQd, H-NMR) are applied to highlight the extracting efficiency of the tested mixtures regarding the phenolic content and composition. The use of acetonitrile does not have a clear positive effect that could compensate its higher cost, commercial availability, and toxicity. The findings justify further why methanol:water, 80:20 v/v should be retained in a future IOC protocol for the accurate and repeatable determination of total Htyr and Tyr content, which is necessary to support the health claim for “olive oil polyphenols.”. Practical Applications: The development of a harmonized and standardized methodology for the determination of total Htyr and Tyr content in an explicit manner is a request of the olive oil sector. A tool that can be introduced easily in the olive industry and official laboratories for the control of the label that bears a health claim for “olive oil polyphenols,” is also requested by the consumers and the IOC. In this view, the present study contributes to the cornerstone that is the standardization of the extraction solvent. Methanol:water 80:20 v/v, should be retained in an International Olive Council protocol for the accurate and repeatable determination of total hydroxytyrosol and tyrosol content necessary to support the health claim for “olive oil polyphenols”. If the total hydroxytyrosol and tyrosol content is determined after hydrolysis of the polar fraction no effect of artifact formation in the quantitation should be expected., H2020 Societal Challenges. Grant Number: 635690

Podeu consultar el III Workshop anual INSA-UB complet a: http://hdl.handle.net/2445/118993, Sessió 2. Pòster núm. 16

Liquid chromatography-electrospray-tandem mass spectrometry (LC-ESI-MS/MS) was applied to the analysis and authentication of fruit-based products and fruit-based pharmaceutical preparations. A Kinetex C18 reversed-phase column under gradient elution with 0.1 % formic acid aqueous solution and methanol mobile phases was used for the simultaneous determination of 26 polyphenols, allowing an acceptable separation in less than 22 min. Instrumental quality parameters such as limits of detection (LOD, values between 12 and 14 μg/L for 19 of the 26 analyzed polyphenols), linearity (r (2) 0.991), run-to-run and day-to-day precisions (relative standard deviation (RSD) values lower than 9.9 and 13.5 %, respectively), and accuracy (relative errors lower than 8 %) were established. A simple extraction method, consisting of a sample sonication with acetone/water/hydrochloric acid (70:29.9:0.1 v/v/v) and centrifugation, was proposed. Two calibration procedures, external calibration using standards prepared in water and standard addition, were evaluated for polyphenol quantification in several grape and cranberry fruits and processed fruit products. For a 95 % confidence level, no statistical differences were observed between the two calibration methods (p values between 0.06 and 0.95), denoting that external calibration was suitable enough for the quantitative analysis of polyphenols in fruit-based products. The proposed LC-ESI-MS/MS method was then applied to the analysis of polyphenols in 23 grape-based and cranberry-based natural products and pharmaceutical preparations. Polyphenolic concentration data was then analyzed by principal component analysis (PCA) to extract information of the most significant profile data contributing to authentication of natural extracts according to their fruit of origin.

Legumes are a well-known source of phytochemicals and are commonly believed to have similar composition between different genera. To date, there are no studies evaluating changes in legumes to discover those compounds that help to discriminate for food quality and authenticity. The aim of this work was to characterize and make a comparative analysis of the composition of bioactive compounds between Cicer arietinum L. (chickpea), Lens culinaris L. (lentil) and Phaseolus vulgaris L. (white bean) through an LC-MS-Orbitrap metabolomic approach to establish which compounds discriminate between the three studied legumes. Untargeted metabolomic analysis was carried out by LC-MS-Orbitrap from extracts of freeze-dried legumes prepared from pre-cooked canned legumes. The metabolomic data treatment and statistical analysis were realized by using MAIT R's package, and final identification and characterization was done using MSn experiments. Fold-change evaluation was made through Metaboanalyst 4.0. Results showed 43 identified and characterized compounds displaying differences between the three legumes. Polyphenols, mainly flavonol and flavanol compounds, were the main group with 30 identified compounds, followed by α-galactosides (n = 5). Fatty acyls, prenol lipids, a nucleoside and organic compounds were also characterized. The fold-change analysis showed flavanols as the wider class of discriminative compounds of lentils compared to the other legumes; prenol lipids and eucomic acids were the most discriminative compounds of beans versus other legumes and several phenolic acids (such as primeveroside salycilic), kaempferol derivatives, coumesterol and α-galactosides were the most discriminative compounds of chickpeas. This study highlights the applicability of metabolomics for evaluating which are the characteristic compounds of the different legumes. In addition, it describes the future application of metabolomics as tool for the quality control of foods and authentication of different kinds of legumes.

Fortification of food products with iron is a common strategy to prevent or overcome iron deficiency. However, any form of iron is a pro-oxidant and its addition will cause off-flavours and reduce a product's shelf life. A highly bioavailable heme iron ingredient was selected to fortify a chocolate cream used to fill sandwich-type cookies. Two different strategies were assessed for avoiding the heme iron catalytic effect on lipid oxidation: ascorbyl palmitate addition and co-spray-drying of heme iron with calcium caseinate. Oxidation development and sensory acceptability were monitored in the cookies over one-year of storage at room temperature in the dark. The addition of ascorbyl palmitate provided protection against oxidation and loss of tocopherols and tocotrienols during the preparation of cookies. In general, ascorbyl palmitate, either alone or in combination with the co-spray-dried heme iron, prevented primary oxidation and hexanal formation during storage. The combination of both strategies resulted in cookies that were acceptable from a sensory point of view after 1year of storage.

A capillary zone electrophoresis (CZE) method for the simultaneous determination of 20 polyphenols in wine was developed. The separation was performed using fused-silica capillaries of 75 μm i.d. and a 30 mM sodium tretraborate buffer solution at pH 9.2 with 5% isopropanol as a background electrolyte. A capillary voltage of +25 kV with pressure-assisted (3.5 kPa) separation from minute 18 was applied, thus achieving a total analysis time of25 min. Instrumental quality parameters such as limits of detection (LOD, values between 0.3 and 2.6 mg/L), linearity (r(2)0.990), and run-to-run and day-to-day precisions (RSD values lower than 6.5 and 15.7%, respectively) were established. Three different calibration procedures were evaluated for polyphenol quantitation in wines: external calibration using standards prepared in Milli-Q water, standard addition, and pseudomatrix-matched calibration using wine as a matrix. For a 95% confidence level, no statistical differences were observed, in general, between the three calibration methods (p values between 0.11 and 0.84), whereas for some specific polyphenols, such as cinnamic acid, syringic acid, and gallic acid, results were not comparable when external calibration was used. The CZE method using pseudomatrix-matched calibration was then proposed and applied to the analysis of polyphenols in 49 Spanish wines, showing satisfactory results and a wide compositional variation between wines. Electrophoretic profiles and other compositional data (e.g., peak areas of selected peaks) were considered as fingerprints of wines to be used for characterization and classification purposes. The corresponding data were analyzed by principal component analysis (PCA) to extract information on the most significant features contributing to wine discrimination according to their origins. Results showed that a reasonable distribution of wines depending on the elaboration areas was found, tyrosol and gallic, protocatechuic, p-coumaric, and caffeic acids being some representative discriminant compounds.

Analytical strategies for screening, quantitation and confirmation of a group of 100 pesticides in fruit and vegetable samples by LC-MS and LC-MS/MS were developed. The pesticides studied belong to different chemical families of herbicides, insecticides and fungicides. A selection of some degradation products was also included. Chromatographic separation was performed using a Zorbax Eclipse XDB-C8 column (150 mm × 4.6 mm and 5 µm particle size), and gradient elution with acetonitrile-water (both with 0.1% formic acid) as mobile phase. LC-MS/MS using highly-selective selected reaction monitoring (H-SRM) acquisition mode monitoring two transitions for each compound showed to be the most sensitive methodology. Quantitation was carried out using matrix-matched standard calibration and good linearity of response was demonstrated (r > 0.998). Limits of detection (by acquiring two transitions and with the ion-ratio requirements) ranged between 0.01 and 20 µg/kg were obtained. So, in general, the sensitivity achieved meets the maximum residue levels (MRLs) established by the European Union regulation for food monitoring programs. Pesticide confirmation was carried out following European Union guidelines. In order to prevent false-positives, further confirmatory strategies were proposed. LC-MS in highly-selective selected ion monitoring (H-SIM) mode with accurate mass measurement was used to obtain an orthogonal criterion (exact mass) for confirmation. Accurate mass measurements were always bellow 0.9 mDa for almost all pesticides studied (similar to those described with TOF instruments). A user reversed energy ramp (RER) product ion scan spectra library was generated by means of a data dependent analysis for routine library searching of pesticides. The combination of LC-MS/MS in H-SRM mode and the generation of the RER product ion scan spectra and library search were then used to achieve further confirmation on pesticide analysis. The LC-MS and LC-MS/MS strategies developed were successfully applied for the analysis and confirmation of pesticides in different types of fruit and vegetables samples, and examples of the screening, quantitation and confirmation of pesticides in these samples are shown in this work.

This work focuses on the influence of the selected LC-HRMS platform on the final annotated compounds in non-targeted metabolomics. Two platforms that differed in columns, mobile phases, gradients, chromatographs, mass spectrometers (Orbitrap [Platform#1] and Q-TOF [Platform#2]), data processing and marker selection protocols were compared. A total of 42 wines samples from three different protected denomination of origin (PDO) were analyzed. At the feature level, good (O)PLS-DA models were obtained for both platforms (Q2[Platform#1] = 0.89, 0.83 and 0.72; Q2[Platform#2] = 0.86, 0.86 and 0.77 for Penedes, Ribera del Duero and Rioja wines respectively) with 100% correctly classified samples in all cases. At the annotated metabolite level, platforms proposed 9 and 8 annotated metabolites respectively which were identified by matching standards or the MS/MS spectra of the compounds. At this stage, there was no coincidence among platforms regarding the suggested metabolites. When screened on the raw data, 6 and 5 of these compounds were detected on the other platform with a similar trend. Some of the detected metabolites showed complimentary information when integrated on biological pathways. Through the use of some examples at the annotated metabolite level, possible explanations of this initial divergence on the results are presented. This work shows the complications that may arise on the comparison of non-targeted metabolomics platforms even when metabolite focused approaches are used in the identification. This work was supported by the Spanish Ministerio de Ciencia y Tecnología (project CTQ2008-04776/BQU), Fundació Bancaixa (project P1-1B2010-50) and the Generalitat Valenciana (Research Group of Excellence, Prometeo/2009/054; PrometeoII/2014/023).

Fortification of food products with non-heme or heme iron is a common strategy to overcome nutritional iron deficiency. Heme iron is highly bioavailable but it promotes oxidation, as do other iron forms. Palm oil is widely used in the formulation of bakery products and chocolate fillings. The work reported here aims to delay the onset of oxidation of a palm oil matrix fortified with heme iron, as a model for bakery products, through the use of ascorbyl palmitate (0 and 400 mg/kg) and the co-spray-drying of the heme iron with calcium caseinate in two ratios (heme iron concentrate:caseinate, 2:1 and 1:1, w/w). Primary (peroxide value and lipid hydroperoxide content) and secondary (p-anisidine value and hexanal content) oxidation were measured over one year of storage at room temperature in the dark. The combination of ascorbyl palmitate at 400 mg/kg and the co-spray-dried heme iron in a 1:1 ratio was the treatment that best protected iron fortified samples from oxidation during the storage time. Practical applications: Food fortification with iron has been suggested as a good strategy for overcoming iron deficiency. In this study, a heme iron ingredient has been selected due to its higher bioavailability than inorganic iron forms. Nevertheless, as other iron forms, heme iron is a potent pro-oxidant, which may affect the nutritional value, the sensory properties and shelf life of the fortified product. Thus, in this study the co-spray-drying of the heme iron with several coatings was assessed in order to reduce its pro-oxidant activity. The different heme irons were mixed with palm oil, which is a fat widely used in bakery. The combination of co-spray-dried heme iron and ascorbyl palmitate delayed the onset of oxidation, which demonstrates its effectiveness in future iron fortified bakery products. Palm oil is widely used in the formulation of bakery products and chocolate fillings. Therefore, this matrix can be a useful model for iron fortification in bakery products. In a preliminary study with heme iron fortified sunflower oil, the co-spray-drying of heme iron with different coating agents delayed the oxidation onset during accelerated storage at 60°C (see the figure).The combination of ascorbyl palmitate and the co-spray-drying of heme iron with calcium caseinate at 1:1 ratio (CAS 1:1) prevented oxidation of a heme iron fortified palm oil during storage at room temperature in the dark for one year.

Food and drinking water are the principal routes of exposure to arsenic (As) for humans. More than 50 different naturally occurring As-containing compounds have been identified. Regarding the toxicological aspects of arsenic in food, inorganic arsenic (iAs, (arsenite or As(III) and arsenate or As(V)) is considered to be the most dangerous form and is classified as a nonthreshold, class 1 human carcinogen. The organic forms are mainly considered to be non-toxic. Therefore, species-dependent differences in toxicity must be considered when establishing the maximum tolerated levels in food directives. Recently, maximum levels have been fixed for iAs in rice and rice products in EU legislation. Scientific opinions on arsenic in food were issued by the European Food Safety Authority and the FAO/WHO Joint Expert Committee on Food Additives, focusing on dietary iAs exposure. Both reported the urgent need for further data on As species, particularly iAs data, in food groups that provide a significant contribution to the dietary exposure to iAs. As a general recommendation, dietary exposure to iAs should be reduced. Furthermore, the organisations also called upon further initiatives towards development of validated methods for specific and selective determination of inorganic arsenic in various types of foodstuffs. In view of the above, the main goal of this thesis was to develop and validate robust analytical methodology for the determination of iAs as well as other arsenic species in foodstuffs. As external quality control of the validated methods, the validated methods were tested participating in feasibility studies for the preparation of Certified Reference Materials with certified arsenic species and in proficiency tests for iAs determination The proposed methodology was applied to rice and rice products, infant cereals, cereal-based food, seaweeds, mushrooms, fish, bivalves and crustaceans, providing reliable results in response to demands made by international safety agencies. Additionally, daily dietary exposure to tAs and iAs intake to assess the toxicological implications of the ingestion of the selected foodstuffs was estimated. The main conclusions derived from the work conducted in this doctoral thesis are summarized as follows: - The proposed speciation method was successfully validated according to the ISO/IEC 17025:2005 standard, is sensitive and selective and could be considered fit for purpose, i.e. iAs determination in food. This method is straightforward enough for routine analysis for the determination of toxic iAs and other arsenic species in several foodstuffs, even in challenging matrices such as those of marine origin. Furthermore, since maximum limits of iAs in rice and rice products have recently been established by the European Union, the method could be useful in food control laboratories. - Based on our results on marine foods, wide variability in arsenic species can be expected when dealing with seafood such as seaweeds, bivalves and crustaceans, highlighting the need to carry out speciation to discern the toxic from the non-toxic species. On the other hand, only toxic iAs species were found in cereal products and iAs was the major As compound found in rice products, highlighting the importance of these food groups as a possible source of iAs in rice and cereal-based diets. - All arsenic speciation data obtained in this thesis are useful for assessing the daily intake of arsenic in the Catalan population. Furthermore, these results may contribute to on-going discussions regarding establishing and implementing maximum levels in inorganic arsenic in food commodities, as recommended within the European Union. - The average estimated iAs daily intake in the adult Catalan population is below the EFSA and JECFA BMDL ranges, but given the ratio between iAs intake and some BMDL for distinct end points, the possibility of risk for high consumers of rice and rice products cannot be excluded., El interés en la determinación de arsénico inorgánico (iAs) en los alimentos se debe al amplio reconocimiento de sus efectos tóxicos en los humanos, incluso a bajas concentraciones. Varios métodos de especiación de arsénico se han publicado, sin embargo es necesario establecer su idoneidad para una serie de muestras de alimentos y /o especies de arsénico Además, existe una necesidad urgente de métodos analíticos robustos y validados y adecuados para la determinación de arsénico inorgánico en una gama de productos alimenticios. Esta necesidad se destacó por varias agencias internacionales de seguridad y salud, y por las organizaciones encargadas de establecer los niveles máximos de la iAs en los productos alimenticios. En vista de todo esto, el objetivo principal de esta tesis es desarrollar y validar metodología analítica robusta para la determinación de arsénico inorgánico, así como otras especies de arsénico en alimentos. La metodología propuesta es aplicada a arroz, alimentos a base de cereales, productos infantiles, setas, algas, peces, crustáceos y bivalvos proporcionando resultados fiables como una respuesta a la demanda de las agencias internacionales de seguridad. Las principales conclusiones derivadas del trabajo llevado a cabo en la presente tesis doctoral se resumen a continuación: • El método de especiación propuesto fue validado con éxito de acuerdo con la norma 17025 ISO/IEC: 2005, es sensible y selectivo y podría ser considerado apropiado para su finalidad, es decir, la determinación de iAs en los alimentos. Este método es sencillo para análisis de rutina para la determinación del tóxico iAs y otras especies de arsénico en varios productos alimenticios, incluso en matrices difíciles tales como las de origen marino. Además, debido a que límites máximos de iAs en arroz y productos de arroz han sido recientemente establecidos por la Unión Europea, el método podría ser útil en los laboratorios de control de los alimentos. • La ingesta diaria promedio de iAs estimada en la población adulta Catalana está por debajo de los rangos BMDL de la EFSA y JECFA, pero teniendo en cuenta relación entre la ingesta de iAs y algunos BMDL para distintos puntos finales, la posibilidad de riesgo para los grandes consumidores de arroz y productos de arroz no pueden ser excluidos.

This work introduces the topic of the authentication of cranberry-based products and the detection and quantification of possible adulterations with other raw materials of lower quality. For such a purpose, genuine and adulterated cranberry samples were analyzed by reversed-phase HPLC with UV detection. Sample components were separated using an elution gradient based on 0.1% (v/v) formic acid aqueous solution and methanol as the components of the mobile phase. Chromatograms were recorded at 280, 370 and 520 nm. Data resulting from the injection of pure and adulterated samples, consisting of chromatographic fingerprints at each detection wavelength, were analyzed chemometrically. Preliminary studies by Principal Component Analysis showed that the sample extracts were clearly distributed depending on the extent of adulteration. Data was further treated by Partial Least Square regression to determine the percentages of grape contamination. It was found that even mixture samples containing low percentages of grape could be distinguished from genuine cranberry extracts. Besides, results obtained were highly satisfactory, with overall quantification errors lower than 5%. As a conclusion, the method proposed here resulted in an excellent approach to carry out the authentication of cranberry-based products relying on polyphenolic fingerprints.

The present study reports arsenic analysis in Lentinula edodes, Agaricus bisporus and Pleurotus ostreatus before and after being cooked. Furthermore, arsenic in raw and cooked mushroom was determined in the gastric and gastrointestinal bioaccessible fractions obtained after simulating human digestion by means of an in vitro physiologically based extraction test (PBET). Several certified reference materials (SRM 1568a, SRM 1570a, CRM 7503-a, BC211 and IPE-120) were analysed to evaluate the proposed methods. Total arsenic content was 1393, 181 and 335 μg As kg-1 for L. edodes, A. bisporus and P. ostreatus, respectively, and decreased by between 53% and 71% in boiled mushroom and less than 11% in griddled mushroom. High bioaccessibility was observed in raw, boiled and griddled mushroom, ranging from 74% to 89% and from 80% to 100% for gastric and gastrointestinal extracts, respectively, suggesting the need to consider the potential health risk of consumption of the mushrooms analysed.

A simultaneous derivatization/extraction method followed by liquid chromatography-electrospray-highresolution mass spectrometry for the determination of volatile thiols in hydroalcoholic matrixes wasoptimized and used to identify and quantify volatile thiols in wine and beer samples. The method wasevaluated in terms of sensitivity, precision, accuracy and selectivity. The experimental LOQs of eleventhiols tested ranged between 0.01 ng/L and 10 ng/L. Intra-day relative standard deviation (RSD) wasin general lower than 10% and inter-day RSD ranged between 10% and 30%. Recovery in the model andreal matrixes ranged from 45% to 129%. The method was then applied for the analysis of four white winesand six beers. Five out of the eleven reference thiols were identified and quantified in the samplesanalyzed. The non-target approach, carried out by monitoring the diagnostic ion at m/z 275.9922[C 13 H 10 ONSe] + in the fragmentation spectrum, allowed detecting, in the same samples, fourteennon-target thiols. 2014 Elsevier Ltd. All rights reserved.

Direct solid sample analysis with graphite furnace atomic absorption spectrometry (SS-GF AAS) was investigated initially with the intention of developing a method for the determination of total As in fish and other seafood. A mixture of 0.1% Pd+0.06% Mg+0.06% Triton X-100 was used as the chemical modifier, added in solution over the solid samples, making possible the use of pyrolysis and atomization temperatures of 1200°C and 2400°C, respectively. The sample mass had to be limited to 0.25mg, as the integrated absorbance did not increase further with increasing sample mass. Nevertheless, the recovery of As from several certified reference materials was of the order of 50% lower than the certified value. Strong molecular absorption due to the phosphorus monoxide molecule (PO) was observed with high-resolution continuum source AAS (HR CS AAS), which, however, did not cause any spectral interference. A microwave-assisted digestion with HNO3/H2O2 was also investigated to solve the problem; however, the results obtained for several certified reference materials were statistically not different from those found with direct SS-GF AAS. Accurate values were obtained using inductively coupled plasma mass spectrometry (ICP-MS) to analyze the digested samples, which suggested that organic As compounds are responsible for the low recoveries. HPLC–ICP-MS was used to determine the arsenobetaine (AB) concentration. Accurate results that were not different from the certified values were obtained when the AB concentration was added to the As concentration found by SS-GF AAS for most certified reference materials (CRM) and samples, suggesting that SS-GF AAS could be used as a fast screening procedure for inorganic As determination in fish and seafood.

El beneficio para la salud del consumo diario de al menos 5 raciones entre frutas y hortalizas está bien documentado. En España no se alcanzan los 600 gramos por persona y día que recomienda la Organización Mundial de la Salud (OMS) en sus objetivos de salud pública, por lo que es importante mejorar el acceso a estos alimentos, aprovechar su potencial nutritivo y salvar las barreras para su consumo. Los objetivos de este documento son: facilitar la toma de decisiones responsables con la salud; aprovechar al máximo el valor nutritivo de frutas y hortalizas; ayudar a salvar las barreras para su consumo e informar sobre cómo afecta la conservación, manipulación y cocinado domésticos a su valor nutritivo.Para minimizar la pérdida de nutrientes y mejorar su biodisponibilidad durante la manipulación de frutas y hortalizas, la Asociación para la promoción del consumo de frutas y hortalizas “5 al día” (España) recomienda: evitar almacenamientos prolongados en el refrigerador; aprovechar las capas y hojas exteriores; pelar y/o cortar el alimento justo antes de consumirlo; lavar las piezas enteras y trocearlas posteriormente; controlar el tiempo de remojo de las piezas cortadas; preferir técnicas de cocinado que no requieran contacto directo con el agua; a menor tiempo de cocción, menor pérdida de nutrientes; la fritura correcta conserva muy bien los nutrientes, aunque no debe abusarse de esta técnica; añadir un chorrito de vinagre o de zumo de limón al agua de cocción; aprovechar el agua de los vegetales cocidos para elaborar otros alimentos (ej.: salsas, sopas, purés, etc.), excepto la de acelgas, espinacas o remolacha. La Asociación “5 al día” recomienda aumentar el consumo de frutas y hortalizas, y considera que la pérdida de nutrientes durante su manipulación doméstica no debe entenderse como una barrera para su consumo.

Public concern about pesticides in food and water has increased dramatically in the last two decades. In order to guarantee consumers' health and safety, analytical methods that could provide fast and reliable answers without compromising accuracy and precision are required. Sample treatment is probably the most tedious and time-consuming step in many analytical procedures and, despite the significant advances in chromatographic separations and mass spectrometry techniques, sample treatment is still one of the most important parts of the analytical process for achieving good analytical results. Therefore, over the last years, considerable efforts have been made to simplify the stage and to develop fast, accurate and robust methods which allow the determination of a wide range of pesticides without compromising the integrity of the extraction process. This review article intends to give a short overview of recently developed on-line solid-phase extraction, pre-concentration and clean-up procedures for the determination of pesticides in complex matrices by liquid chromatography-mass spectrometry techniques.

Veterinary medicines are widely administered to farm animals since they keep animals healthy at overcrowded conditions. Nevertheless the continuous administration of medicines to farm animals can frequently lead to the presence of residues of veterinary drugs in consumption products. Amprolium is a quaternary ammonium compound used in the treatment of coccidiosis. In this paper a method based on capillary zone electrophoresis (CZE) to analyze residues of amprolium in eggs was developed and validated for the first time. Parameters such as electrolyte type, concentration and pH were optimized. In order to improve sensitivity, field amplified sample injection (FASI) was used for in-line preconcentration after a quick and simple sample treatment based on SPE (Envi-Carb). During method validation studies using egg samples a matrix interference was found at the migration time of amprolium. This compound was identified as thiamine and confirmed by MSn experiments using capillary electrophoresis coupled to mass spectrometry (CE-MS) with an ion-trap mass analyzer. CZE conditions were re-optimized to separate thiamine from amprolium allowing the quantification of amprolium in eggs at concentrations down to 75 µg Kg-1, which are far below the MRL legislated values.

There is an increasing need for applications in food and environmental areas able to cope with a large number of analytes in very complex matrices. The new analytical procedures demand sensitivity, robustness and high resolution within an acceptable analysis time. The purpose of this review is to describe new trends based on fast liquid chromatography applied to the food and environmental analysis. It includes different column technologies, such as monolithic, sub-2 μm, porous shell, as well as different stationary phases such as reversed phase (C8 and C18), hydrophilic interaction liquid chromatography (HILIC) and fluorinated columns. Additionally, recent sample extraction and clean-up methodologies applied to reduce sample manipulation and total analysis time in food and environmental analysis – QuEChERS ( Quick , Easy , Cheap , Effective , Rugged and Safe ), on line solid phase extraction coupled to ultrahigh pressure liquid chromatography (on line SPE–UHPLC), turbulent flow chromatography (TFC) and molecularly imprinted polymers (MIPs), were also addressed. The advantages and drawbacks of these methodologies applied to the fast and sensitive analyses of food and environmental samples are going to be discussed.

Benzophenone (BP) is one of the many contaminants reported as present in foodstuff due to its migration from food packaging materials. Liquid chromatography tandem mass spectrometry (LC-MS/MS) is acknowledged in the literature as the method of choice for this analysis. However, cases have been reported where the use of this methodology was not enough to unambiguously confirm the presence of a contaminant. In previous work performed by the authors, the unequivocal identification of BP in packaged foods was not possible even when monitoring two m/z transitions, since ion ratio errors higher than 20% were obtained. In order to overcome this analytical problem a fast, sensitive and selective liquid chromatography-high resolution-mass spectrometry (LC-HRMS) methodology has been developed and applied to the analysis of BP in packaged foods. A direct comparison between liquid chromatography high resolution mass spectrometry (LC-HRMS) and LC-MS/MS data indicated better selectivity when working with LC-HRMS at a resolving power of 50,000 FWHM than when monitoring two m/z transitions by LC-MS/MS. The resolving power used enabled the detection and identification of Harman as the compound impeding the confirmation of BP by LC-MS/MS. Similar quantitative results were obtained by an Orbitrap mass analyser (Exactive ¿) and a triple quadrupole mass analyser (TSQ Quantum Ultra AM ¿).

El dia 15 de novembre de 2011, a la fira Expoquimia se celebrà una jornada científica amb el títol «Química alimentària: ciència versus cultura» organitzada per l'Associació Catalana de Ciències de l'Alimentació, amb la col·laboració de la Societat Catalana deQuímica i d'Expoquimia 2011. En aquesta publicació es recullen els aspectes més destacats de les quatre ponències presentades., On November 15th 2011, with in the framework of the trade fair Expoquimia 2011, the Associació Catalana de Ciències de l’Alimentació (Catalan Association of Food Science) and the Societat Catalana de Química (Catalan Society of Chemistry) organised a scientific meeting called “Food chemistry: science vs culture”. The main ideas introduced in the four presentations that took place are presented in this article.

Conditions were established for the separation and analysis of Bisphenol A (BPA), Bisphenol F (BPF), and their diglycidyl ethers, by micellar electrokinetic capillary chromatography (MECC). Good resolution was obtained for all compounds, although in order to achieve the separation of ortho-ortho, ortho-para, and para-para isomers of Bisphenol F diglycidyl ether (BFDGE), BFDGE¿2H2O and BFDGE¿2HCl, it was necessary to use a 25 µm I.D. fused-silica capillary. To increase sensitivity, a field amplified sample injection (FASI)-MECC method was developed using 10 mM sodium dodecyl sulfate (SDS) solution as injection matrix and a 75 µm I.D. fused-silica capillary. Instrumental quality parameters such as limits of detection (0.999), and run-to-run and day-to-day precisions (relative standard deviations (RSD) values lower than 12.5%) were determined. Finally, the suitability of the FASI-MECC method for the analysis of BPA, BPF and their diglycidyl ethers in canned soft-drinks was evaluated. Quantitation was performed by matrix-matched calibration using a plastic-bottled isotonic drink as matrix. The results showed that FASI-MECC is an economic method for the screening and quantitation of these kinds of compounds in soft-drink beverages, with no loss of reproducibility, and effective at concentrations lower than the specific migration level (SML) values established by the European Union.

Micellar electrokinetic chromatography (MEKC) has been applied for the determination of 5-hydroxymethylfurfural in several foodstuffs. A 75 mM phosphate buffer solution at pH 8.0 containing 100 mM sodium dodecylsulphate was used as background electrolyte (BGE), and the separation was performed by applying +25 kV in a 50 μm I.D. uncoated fused-silica capillary. Good linearity over the range 2.5–250 mg kg −1 ( r 2 ⩾ 0.999) and run-to-run and day-to-day precisions at low and medium concentration levels were obtained. Sample limit of detection (0.7 mg kg −1 ) and limit of quantification (2.5 mg kg −1 ) were established by preparing the standards in blank matrix. The procedure was validated by comparing the results with those obtained with liquid chromatography coupled to tandem mass spectrometry (LC–MS/MS). Levels of HMF in 45 different foodstuffs such as breakfast cereals, toasts, honey, orange juice, apple juice, jam, coffee, chocolate and biscuits were determined.

El resveratrol és un component del vi, el qual té uns potencials efectes beneficiosos en malalties relacionades amb l'envelliment com poden ser el càncer, la malaltia cardiovascular, la diabetis i les malalties neurodegeneratives, augmentant l'esperança de vida d'organismes simples i mamífers actuant com a mimetic de la restricció calòrica. Els biomarcadors nutricionals poden ser una millor mesura de l'exposició dietètica que les dades estimades mitjançant enquestes alimentàries, perquè tenen tres grans avantatges envers les enquestes : a) els biomarcadors nutricionals són més precisos; b) les dades dietètiques són normalment més inadequades degut a les limitacions en les dades de composició dels aliments; c) l'anàlisi del biomarcador proporciona una mesura més pròxima del nutrient específic que les dades dietètiques perquè és una mesura integrada del metabolisme del component. Un biomarcador ideal ha de ser quantitativament robust, específic, sensible als canvis en la ingesta del component dietètic, i un període de vida mig adequat. La hipòtesis d'aquesta tesi doctoral ha estat la de determinar els metabòlits urinaris del resveratrol (URM) com a biomarcadors útils de la consumició del vi.Es van realitzar dos estudis clínics aleatoritzats, creuats, prospectius. En el primer estudi 10 homes sans van consumir 30g d'etanol/dia en forma de cava o ginebra durant 28 dies. En el segon assaig, 10 dones sanes van consumir 20g d'etanol/dia en forma de vi blanc o negre durant 28 dies. A més a més es van analitzar 1000 participants free-living en un estudi per avaluar efectes d'una dieta mediterrània en la prevenció primària de la malaltia cardiovascular (estudi de PREDIMED). Les anàlisis de URM foren realitzades mitjançant LC-MS/MS després d'una extracció en fase sòlida. Es van utilitzar els valors predictius i la corba ROC per determinar l'exactitud de la prova diagnòstica.S'utilitza una metodologia robusta LC-MS/MS per determinar el URM en humans. La dosis diària de consumició de vi va ser correlacionada positivament amb els URM (r = 0.895, p< 0.001). En l'anàlisi estadístic mitjançant corba ROC es van obtenir els valors òptims de sensibilitat, la especificitat i els valors predictius.També es van estimar ingesta dietètica del resveratrol i del piceid (R&P) en la població adulta espanyola. Per aquest propòsit es va compilar una completa base de dades de composició d'aliments de R&P en aliments d'origen espanyol. L'estudi on es va aplicar va ser la cohort espanyola de l'estudi European Prospective Investigation into Cancer and nutrition (EPIC), on participen 40685 voluntaris. La mediana estimada i la mitjana de R&P van ser 100 i 933 microgr./d respectivament. La font més important de R&P van ser els vins (98.4%).Per tant, els URM se poden utilitzar com a una mesura objectiva i útil del consum de vi en estudios clínics i garns estudis epidemiològics free-living., Resveratrol, a constituent of wine, has been shown to have beneficial effects on diseases of ageing including cancer, cardiovascular disease, diabetes and neurodegeneration, as well as increase stress resistance and extent the lifespan of organisms and mammals as caloric restriction mimetic. Nutritional biomarkers may be a better measure of dietary exposure than self-reported dietary data, because they have three distinct advantages over dietary data: a) biochemical markers of some nutrient intake are more precise than dietary assessment; b) dietary data are often inadequate because of limitation in food composition data; c) biomarker analysis provides a more proximal measure of specific nutrient intake than dietary data because it is useful as an integrated measure of the metabolism of the component. An ideal biomarker should be quantitatively robust, specific, sensitive to changes in intake of the dietary component, and have an adequate half-life. The hypothesis of this thesis was to assess urinary resveratrol metabolites (URM) as useful biomarkers of wine consumption.We performed two randomized, crossover trials and a cohort study. In the first study 10 healthy men consumed 30 g ethanol/day as sparkling wine or gin for 28 days. In the second trial, 10 healthy women consumed 20 g ethanol/day as white or red wine for 28 days. Furthermore 1000 free living participants in a study on the effects of a Mediterranean diet on primary prevention of cardiovascular disease (PREDIMED study) were also evaluated. Analyses of URM were carried out by LC-MS/MS after a solid phase extraction. We used predictive values and ROC curve analyses to assess the diagnostic accuracy.A robust methodology using LC-MS/MS analysis was applied to determinate the URM in humans. The reported daily dose of wine consumption was correlated positively with URM (r = 0.895, pWe also estimated the dietary intake of resveratrol and piceid (R&P) in the Spanish adult population. For this purpose, a food composition data base (FCDB) of R&P in Spanish foods was compiled. The study included 40685 subjects a who were included in the European Prospective Investigation into Cancer and nutrition (EPIC)-Spain cohort. The estimated median and mean of R&P intake were 100 and 933 microgr./d respectively. The most important source of R&P were wines (98·4%).URM can be used as an objective an useful measure of wine consumption in clinical and large free-living epidemiologic studies.

Resveratrol has been shown to have beneficial effects on diseases related to oxidant and/or inflammatory processes and extends the lifespan of simple organisms including rodents. The objective of the present study was to estimate the dietary intake of resveratrol and piceid (R&P) present in foods, and to identify the principal dietary sources of these compounds in the Spanish adult population. For this purpose, a food composition database (FCDB) of R&P in Spanish foods was compiled. The study included 40 685 subjects aged 35–64 years from northern and southern regions of Spain who were included in the European Prospective Investigation into Cancer and Nutrition (EPIC)-Spain cohort. Usual food intake was assessed by personal interviews using a computerised version of a validated diet history method. An FCDB with 160 items was compiled. The estimated median and mean of R&P intake were 100 and 933 μg/d respectively. Approximately, 32 % of the population did not consume R&P. The most abundant of the four stilbenes studied wastrans-piceid (53·6 %), followed bytrans-resveratrol (20·9 %),cis-piceid (19·3 %) andcis-resveratrol (6·2 %). The most important source of R&P was wines (98·4 %) and grape and grape juices (1·6 %), whereas peanuts, pistachios and berries contributed to less than 0·01 %. For this reason the pattern of intake of R&P was similar to the wine pattern. This is the first time that R&P intake has been estimated in a Mediterranean country.

Las frutas y sus derivados (especialmente zumos y néctares) y como principal bebida alcohólica el vino, tienen una gran importancia económica y social en los países mediterráneos. La definición de los parámetros de calidad aromática es de gran interés tanto para los organismos legislativos como para las empresas productoras. El objetivo principal de este trabajo ha sido la caracterización aromática de bebidas derivadas de fruta. Para eso, primero hay que establecer un método analítico que sea adecuado para el control de calidad, por tanto tiene que ser rápido, fácil, económico y respetuoso con el medio ambiente. En la elaboración de los derivados de fruta se utilizan de forma habitual enzimas pectolíticos, lo que supone una modificación de la composición en polisacáridos y, dado el papel de estos en la retención de los compuestos volátiles, esto puede afectar a la percepción. Por tanto el segundo objetivo ha sido estudiar la influencia de los polisacáridos sobre la composición volátil.Después de una revisión detallada se ha escogido como método analítico la Microextracción en Fase Sólida (SPME) con la fibra de PDMS. Esta técnica se ha aplicado a zumos y néctares de albaricoque, melocotón y pera de distinto origen (convencional y biológico). Se ha identificado un amplio perfil aromático y a partir de estos resultados se ha establecido la capacidad discriminante del método ya que a partir de los compuestos volátiles se han separado las muestras según la fruta y además según el tipo de producción. También se ha aplicado el método a dos cavas (vino espumoso de calidad elaborado en una región determinada) de distinto tiempo de envejecimiento. Se han ensayado dos fibras, la PDMS y, la más novedosa de DVB-CAR-PDMS. El método de SPME con la fibra de triple recubrimiento, permite discriminar los cavas según un parámetro mucho más exigente como son los meses de rima. Para estudiar la influencia de los polisacáridos sobre la composición volátil es necesario determinar la composición en polisacáridos según su peso molecular, mediante un método ventajoso para ser utilizado rutinariamente. El método escogido ha sido la cromatografía de gel permeación (GPC). La capacidad discriminante de este método se ha demostrado en zumos y néctares comerciales, diferenciando entre el origen convencional y biológico de estos zumos y, en mostos de uva diferenciando entre extractos que provienen de vides con distinta producción (kg/ha). Finalmente, los dos métodos han sido aplicados a zumos de albaricoque, melocotón y pera elaborados en el laboratorio de los cuales se han obtenido tres tipos: los control (sin tratamiento enzimático), un segundo zumo al que se ha aplicado un enzima para facilitar la extracción y finalmente un tercer grupo al que se ha aplicado un enzima para clarificar. La composición en polisacáridos varía en función de la fruta estudiada e incluso de la variedad, pero en general los enzimas incrementan la composición en polisacáridos de menor peso molecular. Se han identificado numerosas familias químicas en el perfil volátil obtenido por SPME y fibra DVB-CAR-PDMS y al estudiar el efecto de los enzimas sobre los volátiles, el tratamiento parece ser útil para los zumos de albaricoque dando lugar a zumos más ricos en terpenos y norisoprenoides (de sabor agradable); mientras que parece no favorecer aromáticamente los zumos de melocotón y pera ya que disminuyen las lactonas y los ésteres de decadienoato que son los compuestos impacto de estas frutas, respectivamente., Fruits and its derivatives have a great social and economic importance in the Mediterranean Countries. The present study aims at the identification of characteristic volatile compounds in fruit derived beverages using a rapid, easy, economic and respectful with the environment method. The influence of the polysaccharides to the volatile compounds was also examined.Solid Phase Microextraction (SPME) using PDMS fibers was the technique established for this study. This extraction method was applied to different commercial juices and nectars, such as apricot, peach and pear, which were processed in an organic and conventional way. A wide range of chemical families were obtained and although the discriminate capacity was checked. Using the same method two different aging series of cava (Spanish sparkling wine) were analyzed. The technique employed was able to differentiate the analyzed cavas according to the ageing time.In order to study the influence of polysaccharides to the volatile composition, Gel Permeation Chromatography (GPC), a molecular weight method, was used. GPC showed a high discriminate capacity not only in grapes of different yields (kg/ha) and different maturation indexes but also in juices and nectars of different origins and production processes, conventional and organic.Finally, the SPME and GPC methods were applied to apricot, peach and pear juices elaborated in the laboratory. After two enzymatic treatments applied during the manufacture of the fruit juices, the behavior of volatile compounds was described. Chemical families, never before identified in these fruits, were found. The enzymes used for the clarification and extraction of fruit juices modified the polysaccharides, and as a result of that the volatile composition. In apricot the enzymes enhanced some varietal compounds, such as terpenes and norisoprenoids. In contrast to apricot, the amount of lactones and decadienoate esters, the character impact compounds of peach and pear, didn't get favored by the enzymes used.

El objetivo de esta Tesis Doctoral fue el estudio de la calidad del boquerón (Engraulis encrasicholus) en función de los cambios sensoriales, químicos y microbiológicos, tanto durante el almacenamiento en hielo del producto no procesado como durante la elaboración de semiconservas. Se validaron técnicas de Análisis por Inyección de Flujo (FIA) para la determinación de trimetilamina (N-TMA) y nitrógeno básico volátil total (N BVT) en boquerón, y se compararon con métodos de referencia. El FIA mostró una linealidad y exactitud equivalente a los métodos de referencia, pero fue más preciso y con la ventaja añadida de su rapidez y menor coste. También se validaron tablas sensoriales específicamente diseñadas para el análisis de boquerón crudo (Quality Index Method, QIM) y cocido. Los esquemas propuestos resultaron adecuados para valorar la frescura del boquerón y mostraron una buena concordancia con los parámetros microbiológicos legalmente establecidos. Se estudiaron parámetros microbiológicos y químicos durante el almacenamiento en hielo del boquerón para establecer límites de rechazo. Los recuentos microbianos incrementaron durante el almacenamiento, siendo los micro/estafilococos el grupo dominante, seguido por Pseudomonas y enterobacterias. Estas últimas determinaron la durabilidad del boquerón almacenado en hielo (5 días). En cuanto a los parámetros químicos, las aminas volátiles (N-TMA y N BVT) no serían adecuadas como indicadoras del grado de frescura, pues no mostraron cambios significativos durante la primera quincena de almacenamiento. La cadaverina, seguida de putrescina y en menor grado de tiramina e histamina fueron las aminas biógenas (AB) de acumulación mayoritaria. La suma de estas cuatro AB se propuso como índice para la valoración de la frescura del boquerón en hielo, estableciéndose el límite de aceptación en 15 mg/kg, concordando con la evaluación sensorial y microbiológica. Además, se estudió la capacidad aminogénica in vitro de bacterias aisladas durante el almacenamiento. Las bacterias Gram (enterobacterias y pseudomonas) fueron productoras de diaminas (putrescina y cadaverina) y se encontraron durante las dos primeras semanas de almacenamiento. Por el contrario, las bacterias Gram + (bacterias del ácido láctico y enterococos) fueron productoras de tiramina y solamente aparecieron en los aislados del final del almacenamiento. No se encontraron bacterias productoras de histamina. La naturaleza mesofílica de las bacterias histaminogénicas explicaría su ausencia en el pescado mantenido en hielo. En semiconservas de anchoas, se constató la importancia de la calidad higiénico-sanitaria de la materia prima como factor crítico para la acumulación de AB y N-BVT durante la elaboración. En anchoas en sal, se observó que el retraso en la evisceración, que se realiza en situaciones de gran volumen de producción, provoca un aumento en los niveles de algunas AB. Durante la elaboración de boquerones marinados en vinagre, la formación de aminas volátiles y biógenas no fue muy importante, sin embargo puede haber formación de AB durante el almacenamiento, probablemente como consecuencia de la contaminación microbiana derivada de la manipulación que supone el fileteado y envasado. Existe un importante efecto extractor del vinagre sobre las aminas, por lo que sus contenidos en el músculo del pescado pueden no ser representativos del estado higiénico de las materias primas y su posterior manipulación. Finalmente, se evaluó la posible implicación de los contenidos de AB de las muestras estudiadas en la salud del consumidor, concluyendo que los contenidos son insuficientes para provocar una intoxicación directa en individuos adultos sanos. Sólo en individuos susceptibles, con tendencia a migrañas o bajo tratamiento con medicamentos IMAO podría ser recomendable limitar el consumo de semiconservas de anchoas, pues ocasionalmente presentan niveles considerables de tiramina., The objective of this Doctoral Thesis was to study the quality of anchovy (Engraulis encrasicholus) in relation to sensory, chemical and microbiological changes, in non-processed fish and during semi-preserves elaboration. Flow Injection/Gass Difussion (FIA) techniques to determine trimethylamine (TMA N) and Total Volatile Basic Nitrogen (TVB N) were validated, resulting as satisfactory as reference methods, but more rapid and simple. Moreover, sensory schemes were specifically developed for raw (Quality Index Method, QIM) and cooked anchovy.During the ice storage of anchovies, volatile amines hardly increased. Therefore, they are not suitable for freshness assessment. The main biogenic amines (BA) increasing in anchovy during the iced storage were cadaverine followed by putrescine, but also tyramine and histamine. The sum of them resulted a reliable index of freshness assessment, with a limit of acceptability set at 15 mg/kg. Gram - bacteria, producing diamines, were found among the isolates from the first two weeks of ice storage; whereas Gram + bacteria produced tyramine and were found only at the end of the storage. No histaminogenic isolate was found.Concerning semi-preserves, the hygienic quality of raw material was a critical factor determining the aminogenesis. During the salt ripening, a delay of the gutting increased formation of some BA. Vinegar marinating of anchovies resulted in a little accumulation of amines, but it could occur during the storage due to contamination during manipulation when filleting and packaging. Since an important extractive effect of the vinegar over these compounds was observed, neither BA nor volatile amines would representative of the hygiene status of the raw material or manipulation.Finally, from the amine contents found in commercial products, the risk of direct intoxication was considered low. Nevertheless, sensitive individuals or under IMAO treatment should avoid salt-ripened anchovies, due the occurrence of variable but sometimes high levels of tyramine.

Las aminas heterocíclicas (HAs) son compuestos genotóxicos formados durante el cocinado de alimentos ricos en proteínas. Su determinación está dificultada por el bajo nivel de concentración de estos analitos y por la complejidad de la matriz, por lo que es necesario disponer de metodología adecuada. El principal objetivo de esta tesis doctoral ha sido por tanto el desarrollo de métodos analíticos que permitan cuantificar fiablemente las aminas heterocíclicas presentes en los alimentos.En primer lugar, nuestro trabajo se dirigió hacia el desarrollo de un método de tratamiento de muestra que, aún siendo más sencillo que los normalmente utilizados, nos permitiese analizar un elevado número de compuestos. Con este fin, se evaluaron varios de los métodos propuestos en la bibliografía y se estudió el cambio de las disoluciones de lavado y de los adsorbentes utilizados.A continuación, se realizó el acoplamiento entre la cromatografía de líquidos y la espectrometría de masas. Se utilizó un espectrómetro de masas de trampa de iones, y se optimizaron en primer lugar los parámetros de formación y transmisión de los iones. Seguidamente, se optimizaron las condiciones necesarias para realizar la detección mediante espectrometría de masas en tándem, y se evaluaron los parámetros de calidad obtenidos tanto para el modo MS como para el MS/MS.Con el fin de posibilitar la identificación de nuevas HAs en alimentos, se estudiaron los patrones de fragmentación de estos compuestos en espectrometría de masas. En el caso de los aminoimiodazoazaarenos, la fragmentación se produjo principalmente en el anillo imidazólico, con pérdidas de CH3, C2NH3 o CN2H2 entre otras. Para las carbolinas, se produjo la pérdida del grupo amino primario y se fragmentaron los heterociclos, con pérdidas de HCN y CH3CN entre otras. Además, para estos analitos se observó la formación de aductos entre el ion [M+H-NH3]+ y moléculas neutras presentes en la trampa de iones, como agua o acetonitrilo.Para comparar las prestaciones del analizador de trampa de iones y el de triple cuadrupolo, se utilizó también este tipo de instrumento para analizar las HAs mediante LC-MS. Tras la optimización de todos los parámetros instrumentales, se evaluaron los parámetros de calidad en modo SIM y MRM. Los límites de detección obtenidos con el triple cuadrupolo fueron menores que los de la trampa de iones, sin embargo este último analizador permite confirmar la identidad de los analitos mediante la obtención de los espectros de iones producto.A continuación, la metodología analítica desarrollada se validó mediante la participación en diferentes ejercicios interlaboratorio, en los cuales se analizaron una disolución de referencia y varios extractos de carne. En todos los casos, los resultados obtenidos fueron satisfactorios.Para finalizar, se estimó la ingesta en España derivada del consumo de ternera a la plancha, alimento seleccionado con este fin por ser uno de los más consumidos. Para ello, se analizaron varias muestras, una de ellas cocinada por nosotros y otras obtenidas de restaurantes. En todas las muestras se encontraron varias HAs a niveles de concentración de entre 0,2 y 21 ng g-1.