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Texture-modified pumpkin was developed by using vacuum enzyme impregnation to soften texture to tolerable limits for the elderly population with swallowing and chewing difficulties. The impregnation process, and macrostructural and microstructural enzyme action, were explored by the laser light backscattering imaging technique and a microscopic study by digital image analysis. Texture was analyzed by a compression assay. The effect of enzyme treatment on antioxidant capacity and sugar content was evaluated and compared to the traditional cooking effect. Image analysis data demonstrated the effectiveness of the impregnation process and enzyme action on plant cell walls. Enzyme-treated samples at the end of the process had lower stiffness values with no fracture point, significantly greater antioxidant capacity and significantly lower total and reducing sugars contents than traditionally cooked pumpkins. The results herein obtained demonstrate the capability of using vacuum impregnation treatment with enzymes to soften pumpkins and their positive effects on antioxidant capacity and sugar content to develop safe and sensory-accepted texture-modified products for specific elderly populations.

Fermented vegetables are produced by the growth of different microorganisms present in raw products. Yeasts are essential in food fermentations, but they are also potential spoilage agents that can cause several alterations to the final product. This review provides an overview of the most relevant spoilage yeasts present in fermented vegetables, such as table olives, fermented pickles, and sauerkraut, and the strategies that can be followed to prevent their presence in the final product by extending their shelf life. Conventional treatments have been applied for years to fermented products to reduce or control microbial contamination. In this group, although the application of thermal treatments and the use of chemical additives are remarkable, these technologies have some drawbacks. Nowadays, the food industry seeks techniques that are lethal to spoilage microorganisms, but have no adverse effects on the nutritional value, organoleptic characteristics, and beneficial product microbiota. Non-thermal technologies, such as high hydrostatic pressure, UV-C light, and electrolyzed oxidizing water treatments, applied alone or combined, are effective alternatives to conventional preservation treatments to achieve secure fermented vegetables with a high quality.

[EN] Inactivation of bacterial spores is a key objective for developing novel food preservation technologies. In this work, the removal properties of filtering materials based on silica microparticles functionalized with essential oil components (EOCs) (carvacrol, eugenol, thymol, and vanillin) against Bacillus subtilis, a spore-forming bacterium, in two liquid matrices were investigated. The viability of vegetative cells and spores after treatment was also evaluated. The results exhibited marked removal effectiveness against B. subtilis vegetative cells and spores after filtration with the different silica supports coated with EOCs in either sterile water or nutrient broth, with reductions of 3.2 to 4.9 log units and 3.7 to 5.0 log units for vegetative cells and spores, respectively. The fluorescent viability images revealed the poor viability of the treated B. subtilis vegetative cells and spores due to damage to the cell envelope when coming into contact with the immobilized antimicrobials. The culture counts results revealed the great inhibitory capacity of the EOC-functionalized silica microparticles against B. subtilis vegetative cells and spores after a single filtration. Hence, the present work suggests the feasibility of using EOC-functionalized supports as filtering aids to enhance the microbial quality of liquid matrices with spore-forming microorganisms. Practical Application The developed antimicrobial-coated filters have shown remarkable removal properties against an important spore-forming bacterium in food industry. These filters may be used as a potential sterilization technique for preservation of different beverages alone or in combination with other mild-thermal or nonthermal techniques., The authors gratefully acknowledge the financial support from the Ministerio de Ciencia, Innovacion y Universidades, the Agencia Estatal de Investigacion and FEDER-EU (Project RTI2018-101599-B-C21). M.R.R. acknowledges the Generalitat Valenciana for her postdoctoral fellowship (APOSTD/2019/118)

To address concerns about the biocompatibility of novel phenolic immobilization-based food preservatives, their impact on the composition and metabonomic profile of a defined community of human gut microbiota was evaluated. Three phenolics (eugenol, vanillin and ferulic acid) presented in two forms (free or immobilized on different supports) were tested at two concentration levels (0.5 and 2 mg/mL). Free eugenol was the phenolic with the greatest impact on gut microbiota, with a remarkable increase in the abundance of Lachnospiraceae and Akkermansiaceae families. In contrast, immobilized phenolics produced an increase in the abundance of Bacteroides with a reduction in the ratio of Firmicutes to Bacteroidetes. The metabonomic profile was also affected by free and immobilized phenolics differently in terms of fermentation by-products and phenolic biotransformation metabolites. Thus the results suggest the importance of evaluating the impact of new compounds or materials added to food on human gut microbiota and their potential use to modulate microbiota composition.

[EN] Alkalization is a crucial process during cocoa processing to reduce its bitterness, improve solubility and develop color. Alkalization can be performed out at several points of the process (nib or cake), with different agents and at various intensities. All these variables may affect cocoa properties, but also physico-chemical and sensory properties of derived products (i.e. cakes). This work aims to evaluate the impact of alkalization type (nib vs. cake), alkalizing agent (K2CO3, NaHCO3 and KOH) and process intensity (mild and strong) on the physicochemical and sensory properties of sponge cakes. For this aim, 8 different alkalized powders were industrially produced and used in the preparation of sponge cakes. Alkalizing conditions significantly affected cocoa properties (pH, color, sensory properties) and those of the corresponding cakes (cake doughs color and rheology, as well as baked cake color and texture). In general, doughs prepared with cocoas alkalized under strong conditions were a 55 % darker and a 15 % less elastic. After baking, the corresponding cakes were a 17 % darker (L*) and a 12 % harder in texture. Despite these differences, all the cakes were equally rated by consumers in sensory terms demonstrating that for this application, alkalization variables do not condition consumer acceptability., The authors wish to acknowledge the financial assistance provided by the Ministerio de Economia, Industria y Competitividad (Spanish Government) and the European Regional Development Fund (Project RTC-2016-5241-2). We also thank Helen Warburton for editing the English style.

The development of novel food preservatives based on natural antimicrobials such as phenolic compounds is increasing, but their safety should be established before use, including evaluating their impact on the gut microbiota. This work explored the influence of antimicrobial phenolics presented in different forms on selected human gut microbiota members through in vitro susceptibility tests. The bacteria tested exhibited a wide range of susceptibilities to phenolics depending on the molecule structure and mode of administration. Agathobacter rectalis and Clostridium spiroforme, members of the phylum Firmicutes, were the most sensitive strains. Susceptibility was strain- and species-specific, suggesting that it may not be possible to easily extrapolate results across the human microbiome in general. Species of other phyla including Bacteroidetes, Actinobacteria, Proteobacteria and Verrucomicrobia were more resistant than Firmicutes, with growth of some strains even enhanced. Our results provide insights into the biocompatibility of free and immobilized phenolics as potential food additives.

[EN] The capability of laser-backscattering imaging technique as a non-destructive method to control the effect of fat on curdling process phases was studied. It was based on capturing images of the diffraction patterns generated by a laser-matrix interaction, from which data were acquired. The studied phases were: raw material inspection; curdling monitoring; fresh curd inspection and curd storage monitoring. Milk was used with three different fat contents (0, 1.5 and 3.5%). An extra category of 1.5% fat without lactose was added to test the effect of modification on other compounds. All the phases were characterised by a destructive analysis (rheology, texture profile analysis, syneresis) to study both the evolution of the physical properties during the process and the relation to imaging data. Images successfully captured the variance generated by fat content and physical modifications. Differences in fat content were distinguished for raw material and fresh curd despite lack of lactose. Curdling monitoring also allowed the fat effect to be characterised and coagulation time to be established. Matrix evolution during storage was modelled from imaging for 24 h and 96 h. Imaging data correlated with syneresis evolution and texture features. The obtained results showed that laser-backscattering imaging was capable of capturing the effect of both fat and physical changes on each processing phase, which implies that this technique can be employed as a common system for independent phase control, The authors gratefully acknowledge financial support from the Universitat Politecnica de Valencia

[EN] Traditional alkalization, essential for darkening color, modifying flavor and increasing cocoa powder solubility, is a discontinuous time-consuming technique that employs considerable energy. We herein propose extrusion as a promising alternative to improve and increase the sustainability of the traditional process. The aims of this work were twofold: on the one hand, to characterise the effects of extrusion on alkalised cocoa physico-chemical features; on the other hand, to determine if alkalized powders possess similar characteristics to those obtained by conventional treatment. The results showed that alkali was the main variable to increase pH and to diminish color. Compared to commercial samples, the developed cocoas had darker colors than, and similar sensory properties to, their reference commercial cocoas. These findings confirm that extrusion is suitable for producing high sensory acceptable alkalized products quickly, sustainably and continuously., This work was supported by the Spanish Government and European Regional Development Fund (Project RTC-2016-5241-2).

[EN] Cocoa (Theobroma cacao L.) and its derivatives are appreciated for their aroma, color, and healthy properties, and are commodities of high economic value worldwide. Wide ranges of conventional methods have been used for years to guarantee cocoa quality. Recently, however, demand for global cocoa and the requirements of sensory, functional, and safety cocoa attributes have changed. On the one hand, society and health authorities are increasingly demanding new more accurate quality control tests, including not only the analysis of physicochemical and sensory parameters, but also determinations of functional compounds and contaminants (some of which come in trace quantities). On the other hand, increased production forces industries to seek quality control techniques based on fast, nondestructive online methods. Finally, an increase in global cocoa demand and a consequent rise in prices can lead to future cases of fraud. For this reason, new analytes, technologies, and ways to analyze data are being researched, developed, and implemented into research or quality laboratories to control cocoa quality and authenticity. The main advances made in destructive techniques focus on developing new and more sensitive methods such as chromatographic analysis to detect metabolites and contaminants in trace quantities. These methods are used to assess cocoa quality; study new functional properties; control cocoa authenticity; or detect frequent emerging frauds. Regarding nondestructive methods, spectroscopy is the most explored technique, which is conducted within the near infrared range, and also within the medium infrared range to a lesser extent. It is applied mainly in the postharvest stage of cocoa beans to analyze different biochemical parameters or to assess the authenticity of cocoa and its derivatives., The authors wish to acknowledge the financial assistance provided by the Spanish Government and European Regional Development Fund (Project RTC-2016-5241-2). Maribel Quelal Vásconez thanks the Ministry Higher Education, Science, Technology, and Innovation (SENESCYT) of the Republic of Ecuador for her PhD grant.

Pathogenic and spoilage microorganisms can adhere to, and grow on, food surfaces, equipment and processing environments, which results in biofilm structures. Considering the role of biofilm in food spoilage and safety, inhibition of biofilm formation by naturally-occurring antimicrobial compounds is expected to be an alternative to traditional sanitisers. This study aimed to evaluate the diversity of the microbiota attached to food contact surfaces in the meat industry in Turkey, and to assess the antimicrobial and antibiofilm properties of essential oil components against presumptive isolated pathogens. To do so, conventional and molecular methods were use to identify isolates. Nine Gram-positive isolates were classified as Listeria grayi, Lactobacillus paracasei and Staphylococcus warneri. Eleven Gram-negative bacteria were identified with species Escherichia coli and Acinetobacter baumannii. Given the potential pathogenicity of the Gram-negative species, their biofilm forming capability was also analysed, which displayed moderate and strong abilities. The antimicrobial and antibiofilm activity of natural antimicrobials was assessed, and resulted in minimum bactericidal concentrations (MBC) ranging from 0.1 to 0.2 mg/mL for carvacrol and thymol, 0.2–0.5 mg/mL for eugenol, and 2–6 mg/mL for vanillin against A. baumannii and E. coli strains. Lastly, monostrain biofilm formation by A. baumannii and E. coli was substantially reduced by essential oil components at their respective MBC. The findings herein indicate the potential application of essential oil components to avoid biofilm growth on food contact surfaces to prevent food contamination and spoilage.

This study evaluated injection (I) and vacuum impregnation (VI) as the best methods to apply papain, and other important processing conditions (batch, aging and cooking conditions), to obtain soft meat (suitable for people with poor oral health) without disturbing its original shape. Two aging times were evaluated and four cooking conditions by immersion in soup. Meat samples were injected or vacuum-impregned (0.85 kPa) with a papain solution (5% w/v). After cooking, they were analyzed by the compression test, and by image and sensory analyses. The results indicated that by using both methods to apply the enzyme, the obtained meat was suitable for people with poor oral health, even if VI was the better method because it minimized the factors batch, aging and cooking condition. Therefore, the best meat processing method to obtain panelists' highest softness values and the best appreciation was employing aged meat pretreated by VI and cooked at 65 °C for 10 min.

In this work, the influence of different forms of presentation of chitosan in the human gut microbiota with a defined bacterial community was evaluated. First, the susceptibility of individual gut bacterial isolates against chitosan was studied within a concentration range between 0.125 and 1 mg/mL. Then, the impact of chitosan (0.25 and 1 mg/mL) on a defined human gut microbial ecosystem was studied by metagenomic and metabonomic analyses. The results showed that chitosan in its free form had a high impact on individual isolates with a minimum inhibitory concentration below 1 mg/mL for most of the strains studied. In comparison, chitosan immobilized in the different carriers displayed a diverse effect on gut microbiota. The most susceptible strains were Agathobacter rectalis strain 16-6-I 1 FAA, Clostridium spiroforme strain 16-6-I 21 FAA and Mediterraneibacter faecis strain 16-6-I 30 FAA. The impact of the different modes of presentation of chitosan was strain-specific and species-specific when compared to results obtained from analysis of other strains within the genera Agathobacter, Clostridium and Mediterraneibacter, and therefore a study using a defined ecosystem was needed to extrapolate the results. Significant decreases in defined community richness and diversity and changes in metabolic profile were observed after exposure to free chitosan. Free chitosan produced significant reductions in the abundance of the genera Lachnoclostridium, Anaerotignum, Blautia, Enterococcus, Eubacterium and Ruthenibacterium together with a slight decrease of the production of SCFAs, among other fermentation by-products. The immobilized chitosan significantly alleviated the impact caused by the antimicrobial polymer and significantly increased the relative abundance of the Bacteroidetes phylum compared to free chitosan. These results suggest the significance of assessing the impact of new ingredients and materials included in food on the human gut microbiota with models that simulate the gastrointestinal environment, such as in vitro bioreactor systems.

[EN] Phenolic compounds carvacrol, thymol, eugenol, and vanillin are four of the most thoroughly investigated essential oil components given their relevant biological properties. These compounds are generally considered safe for consumption and have been used in a wide range of food and non-food applications. Significant biological properties, including antimicrobial, antioxidant, analgesic, anti-inflammatory, anti-mutagenic, or anti-carcinogenic activity, have been described for these components. They are versatile molecules with wide-ranging potential applications whose use may substantially increase in forthcoming years. However, some in vitro and in vivo studies, and several case reports, have indicated that carvacrol, thymol, and eugenol may have potential toxicological effects. Oxidative stress has been described as the main mechanism underlying their cytotoxic behavior, and mutagenic and genotoxic effects have been occasionally observed. In vivo studies show adverse effects after acute and prolonged carvacrol and thymol exposure in mice, rats, and rabbits, and eugenol has caused pulmonary and renal damage in exposed frogs. In humans, exposure to these three compounds may cause different adverse reactions, including skin irritation, inflammation, ulcer formation, dermatitis, or slow healing. Toxicological vanillin effects have been less reported, although reduced cell viability after exposure to high concentrations has been described. In this context, the possible risks deriving from increased exposure to these components for human health and the environment should be thoroughly revised., The present work was financially supported by the Spanish Government (Project RTI2018-101599-B-C21 (MCUI/AEI/FEDER, EU)), and by a predoctoral program Valithornd (ACIF/2016/139) through the Generalitat Valenciana.

[EN] Essential oil components (EOCs) such as eugenol play a significant role in plant antimicrobial defense. Due to the volatility and general reactivity of these molecules, plants have evolved smart systems for their storage and release, which are key prerequisites for their efficient use. In this study, biomimetic systems for the controlled release of eugenol, inspired by natural plant defense mechanisms, were prepared and their antifungal activity is described. Delivery and antifungal studies of mesoporous silica nanoparticles (MSN) loaded with eugenol and capped with different saccharide gates-starch, maltodextrin, maltose and glucose-against fungus Aspergillus niger-were performed. The maltodextrin- and maltose-capped systems show very low eugenol release in the absence of the fungus Aspergillus niger but high cargo delivery in its presence. The anchored saccharides are degraded by exogenous enzymes, resulting in eugenol release and efficient inhibition of fungal growth., This research was funded by the project NutRisk (Project No: CZ.02.1.01/0.0/0.0/16_019/0000845), the Spanish Government (projects RTI2018-100910-B-C41, RTI2018-101599-B-C22-AR and RTI2018-101599-B-C21-AR (MINECO/FEDER)) and the GeneralitatValenciana (project PROME-TEO 2018/024); by the National Agency for Agricultural Research of the Ministry of Agriculture of the Czech Republic under project Biostore QK21010064; and by the Research Infrastructure METROFOOD-CZ supported by the Ministry of Education, Youth, and Sports of the Czech Republic under project number LM201810. A.B. thanks the Spanish Government for financial support.

[EN] The development of new food preservatives is essential to prevent foodborne outbreaks or food spoilage due to microbial growth, enzymatic activity or oxidation. Furthermore, new compounds that substitute the commonly used synthetic food preservatives are needed to stifle the rising problem of microbial resistance. In this scenario, we report herein, as far as we know, for the first time the use of the zein protein as a gating moiety and its application for the controlled release of essential oil components (EOCs). The design of microdevices consist of mesoporous silica particles loaded with essential oils components (thymol, carvacrol and cinnamaldehyde) and functionalized with the zein (prolamin) protein found in corn as a molecular gate. The zein protein grafted on the synthesized microdevices is degraded by the proteolytic action of bacterial enzymatic secretions with the consequent release of the loaded essential oil components efficiently inhibiting bacterial growth. The results allow us to conclude that the new microdevice presented here loaded with the essential oil component cinnamaldehyde improved the antimicrobial properties of the free compound by decreasing volatility and increasing local concentration., This research was funded by the Government of Spain (projects RTI2018-100910-B-C41, RTI2018-101599-B-C22-AR and RTI2018-101599-B-C21-AR (MCUI/FEDER, EU)) and the Generalitat Valenciana (project PROMETEO 2018/024, grant numbers ACIF/2016/023 and APOSTD/2019/118).

[EN] This study evaluated the flow, viscoelastic and masticatory properties of tailor made pea cream using different hydrocolloids, and the potential effect that saliva could have while chewing. The creams thickened with pectin, carboxymethyl cellulose, tara gum and konjac gum showed the weakest internal gel structure with highest values of loss tangent at 1Hz (0.49 +/- 0.07), slope of log elastic modulus versus log frequency (0.34 +/- 0.05) and maximum capacitance (0.07 +/- 0.02 Pa-1). The samples thickened with commercial hydrocolloids were affected the most by the presence of saliva, with a significant reduction in apparent viscosity at 10 s(-1), that ranged from 1500 mPas until 11000 mPas. These results demonstrate that it is possible to optimize the structure of thickened pea cream for dysphagia by using, for example, carboxymethyl cellulose, tara gum and konjac gum, because they provide a greater viscous component, and, therefore, a bolus that is more easy to swallow., The authors thank the "Ministerio Espanol de Ciencia e Innovaci.on" for the financial support provided through the RTI2018-098842-B-I00 Project.

During wine production and storage, undesired effects can appear mainly due to the microbiological activity of the present microorganisms leading to economic losses. Wine stabilisation is needed for controlling the unwanted microbiological activity to improve wine safety and final quality. Nowadays, a plethora of viticultural and technological solutions is available but, in some cases, the stabilisation process changes the wine sensory profile. The aim of this study was the development of filter aids functionalised with phenolic compounds (PHE) with enhanced antimicrobial properties. The filters’ removal capability was evaluated using white wine inoculated with Acetobacter aceti, Lactobacillus plantarum, Dekkera bruxellensis, Zygosaccharomyces bailii and Saccharomyces cerevisiae. Wine was filtered through PHE-coated filters and the microbial load was determined by plate count. The influence of filtration on the physicochemical wine parameters was also assessed. The removal capacity results showed the PHE-functionalised filters were capable of reducing 3 logarithmic values, being eugenol the most effective compound. The results evidenced different influence of filtration on wine properties according to the immobilised PHE showing that eugenol-functionalised supports had a very low impact on physicochemical parameters. Thus our results support the relevance of using antimicrobial-coated filters at different stages of the winemaking process for wine microbiological stabilisation., The authors gratefully acknowledge the financial support from the Ministerio de Ciencia, Innovación y Universidades, the Agencia Estatal de Investigación and FEDER-EU (Project RTI 2018-101599-B-C21 and Project PID 2019-108722RB-C31). M.R-R. acknowledges the Generalitat Valenciana for her postdoctoral fellowship (APOSTD/2019/118) and E.G-R. is supported by the Sara Borrell Program (CD18CIII/00007), Instituto de Salud Carlos III, Ministerio de Ciencia, Innovación y Universidades.

PurposeThis study aims to evaluate the effect of adding oregano and clove oil-in-water (O/W) nanoemulsions on the physico-chemical, technological and microstructural properties of minimally processed salad dressings during storage at 8 °C and 25 °C.Design/methodology/approachSamples were formulated with either free or encapsulated oregano and clove essential oils in O/W nanoemulsions.FindingsNoticeable differences in the physical stability and microstructure of salad dressings were observed after 11 storage days and were less marked for the samples formulated with encapsulated oregano or clove oils in the O/W nananoemulsions. Moreover, rheological measurements revealed minor changes in the viscoelastic characteristics of the salad dressings containing the O/W nanoemulsions.Originality/valueThese findings confirm the potential of oregano and clove O/W nanoemulsions for use in minimally processed salad dressings as stabilising and technological agents.

[EN] This study aim was to explore the laser backscattering imaging technique's capacity to model the curdling phase in cheese processing. To do so, three different formulas were studied by modifying solute concentration. Textural modifications to the matrix during curdling were characterised by viscosimetry and texture measurements depending on samples' liquid or solid state. This state changed by determining gelation to establish the limits for the liquid and solid phases. The process was also characterised by the imaging technique, which showed dependence on both solute concentration and enzymatic effect on both the previously observed phases. After following multivariate statistical procedures to reduce dimensionality, the imaging results revealed that solute concentration strongly influenced the variance that the imaging technique captured. It reduced the visibility of the phase change in the image parameters. After eliminating this influence, the evolution of the matrix across the liquid and solid phases was modelled. Data were divided into phases and used to successfully predict the matrix status in each phase by multivariate non-linear regression procedures. It was concluded that the laser backscattering imaging technique presented suitable properties to be used for non-destructive continuous curdling process monitoring during the cheese-making process., The authors gratefully acknowledge the financial support from the University Polytechnic of Valencia for Programme "Ayudas para la Contratacion de Doctores para el Acceso al Sistema Espanol de Ciencia, Tecnologia e Innovacion, en Estructuras de Investigacion de la UPV (PAID-10-17)"

[EN] This work evaluated the cytotoxic effect of different EOCs-functionalised silica particle types. The in vitro toxicity of eugenol and vanillin-immobilised SAS, MCM-41 microparticles and MCM-41 nanoparticles was evaluated on HepG2 cells, and compared to free EOCs and pristine materials. The results revealed that free essential oil components and bare silica had a mild cytotoxic effect on HepG2 cells. However, the comparative study showed that free eugenol and vanillin had a milder cytotoxic effect than the equivalent concentrations of immobilised components on the different silica particles, while differences in cell viability between the bare and functionalised particles relied on the type of analysed material. The most cytotoxic materials were eugenol and vanillin-functionalised MCM-41 micro with IC50 values of 0.19 and 0.17 mg/mL, respectively, at 48 h exposure. Differences in cytotoxicity between functionalised particles may be attributed to the density of the functional components on their surface as a result of the functionalisation reaction performance for different materials. The study of the physico-chemical properties of particles demonstrated that cationic nature and increased hydrophobicity could be responsible for promoting cell-particle interactions for the eugenol and vanillin functionalised silica particles, enhancing their cytotoxic behaviour., The authors gratefully acknowledge the financial support from the Spanish government (Project RTI2018-101599-B-C21 (MCUI/AEI/FEDER, EU)). C.F. thanks the Generalitat Valenciana for being funded by the predoctoral programme Vali+d (ACIF/2016/139). M.R.R. also acknowledges the Generalitat Valenciana for her postdoctoral fellowship (APOSTD/2019/118).

[EN] In this work, the biodurability of three silica particle types (synthetic amourphous silica, MCM-41 microparticles, MCM-41 nanoparticles) functionalised with three different essential oil components (carvacrol, eugenol, vanillin) was studied under conditions that represented the human gastrointestinal tract and lysosomal fluid. The effect of particle type, surface immobilised component and mass quantity on the physico-chemical properties of particles and silicon dissolution was determined. Exposure to biological fluids did not bring about changes in the zeta potential values or particle size distribution of the bare or functionalised materials, but the in vitro digestion process partially degraded the structure of the MCM-41 nanoparticles. Functionalisation preserved the structure of the MCM-41 nanoparticles after simulating an in vitro digestion process, and significantly decreased the amount of silicon dissolved after exposing different particles to both physiological conditions, independently of the essential oil component anchored to their surface. The MCM-41 microparticles showed the highest solubility, while synthetic amorphous silica presented the lowest levels of dissolved silicon. The study of these modified silica particles under physiological conditions could help to predict the toxicological behaviour of these new materials., The authors gratefully acknowledge the financial support from the Spanish government (Project RTI2018-101599-B-C21 (MCUI/AEI/FEDER, EU)). Cristina Fuentes also thanks the Generalitat Valenciana for being funded by the predoctoral programme VALi+d (ACIF/2016/139). Maria Ruiz-Rico acknowledges the Generalitat Valenciana for her Postdoctoral Fellowship (APOSTD/2019/118).

[EN] The effect of the presence of food on the incorporation and excretion of silica particles was studied in this work using the biological model Caenorhabditis elegans and image analysis techniques. The experiment was based on two 24-hour phases: exposure and depuration. During exposure, nematodes were maintained for 24 h in liquid medium with silica particles, but some with and others without food. During depuration, nematodes were transferred to medium without particles. Nematodes were analysed by an image analysis in both phases to quantify the properties of particle distributions in nematodes' bodies with time. No differences were found in the proportion of nematodes carrying particles in the exposure phase when food was present. However in the depuration phase, lack of food generated a high proportion of particle carriers. Particle distribution properties were also similar in the exposure phase. Nevertheless, lack of food produced particle accumulation due to decelerated excretion because digestive tube relaxed under these conditions. Thus after the depuration phase, lack of food led particles to persist in digestive tubes. According to these results, intake of silica particles had no retention effects when a food flux was provided, but particles were not easily excreted when the food flux was interrupted., The authors gratefully acknowledge the financial support from the Universitat Polit`ecnica de Valencia by Programme "Ayudas para la Contratacion de Doctores para el Acceso al Sistema Espanol de Ciencia, Tecnologia e Innovacion, en Estructuras de Investigacion de la UPV (PAID-10-17)"and Ministerio de Ciencia, Innovacion y Universidades, the Agencia Estatal de Investigacion and FEDER-EU (Project RTI2018101599-B-C21).

[EN] Growing consumer demand for healthy and nutritious products has motivated scientists and food manufacturers to design novel dairy products with higher fiber levels and lower fat content that are free of chemical additives. Chia seed mucilage (CSM) is a healthy natural gel extensively used as a dietary source of soluble fiber, a bulking agent, and a fat replacer in a large variety of foods. In this study, we evaluated the effect of CSM on the nutritional, technological, and sensory properties of skimmed yogurts. The addition of 7.5% CSM to a yogurt formula lowered the degree of syneresis of the resulting yogurt during storage compared with full-fat yogurts. The nutritive value of the enriched yogurts improved due to higher levels of dietary fiber compared with full-fat and skimmed yogurts. Moreover, rheological measurements revealed greater consistency, firmness, and viscosity, as well as the formation of a highly structured network and better resistance to stress in yogurts containing 7.5% CSM. The sensory acceptance of the yogurts enriched with 7.5% CSM was similar to the reference samples in acidity, creaminess, and viscosity terms. These results confirm the feasibility of using CSM as a fat replacer to design novel skimmed yogurts.

Multispectral imaging represents a powerful technique to maximise data collection and analysis for biological materials. It improves the exploitation and understanding of in vivo/vitro experiments. This work focused on testing the capability of multispectral imaging to characterise the tissue damage produced by alkaline hypochlorite on the body and eggs of the biological model C. elegans. To that end, three synchronisation processes with different final bleach and sodium hydroxide concentrations were performed. The impact of treatments was characterised by measuring egg viability and morphology, besides capturing multispectral images of both nematode bodies and eggs. Multispectral images consisted of seven slices captured from different wavelengths within the visible/infrared spectrum by different light-pass filters. The results showed dependence between increased alkaline hypochlorite concentration and loss of egg viability/morphology. This relation was also observed for the imaging data, which showed alterations to tissue transmittance for all the tested wavelengths for both bodies and eggs. Localised alterations related to alkaline hypochlorite diffusion through anatomical nematode orifices were recognised. Applying multivariate methods to imaging data successfully characterised tissue alterations, from which treatment type was predicted for both nematodes and eggs. Moreover, the alterations recorded by imaging data were also used to predict egg viability regardless of treatment type (0.94). The high correlation between the imaging data from nematodes and eggs with egg viability evidenced multispectral imaging's ability to characterise tissue damage and its possible practical application to study alterations to the tissues of this biological model.

[EN] The rapid and easy classification of almond varieties with similar morphology, different quality properties and, in most cases, different prices is interesting to protect both the almond industry and the consumers from fraud. Therefore, in this work, intact almond kernels from four Spanish varieties (`Guara¿, `Rumbeta¿, `Marcona¿ and `Planeta¿) were analysed using both near infrared (NIR) and attenuated total reflectance Fourier-transform infrared (ATR-FTIR) spectroscopy. After spectra measurement, NIR and ATR-FTIR spectral data were pre-treated and employed to construct two classification methods (partial least square-discriminant analysis (PLS-DA) and quadratic discriminant analysis (QDA)) in order to check their ability to classify almonds according to their variety. The best overall accuracies (94.45%) were obtained with the PLS-DA model of ATR-FTIR and the QDA model of NIR data. These results confirm that both spectroscopic techniques, if the optimal statistical model is selected, are powerful tools to reliably discriminate almonds according to their varieties., Victoria Cortés López thanks the Spanish Ministry of Education, Culture and Sports for the FPU grant (FPU13/04202). The authors wish to thank the cooperative Agricoop for kindly providing the samples used in the experiments. This work was partially funded by INIA and FEDER funds through project RTA2015-00078-00-00.

[EN] Here we report the toxicological evaluation of mesoporous silica particles (MSPs) in the nematode C. elegans. Specifically, we have investigated the effect of bare micro- (M0) and nano-sized (N0) MSPs, and their corresponding functionalized particles with a starch derivative (Glu-N) (M1 and N1, respectively) on C. elegans ageing parameters. The toxicity of MSPs, their impact on C. elegans lifespan, movement capacity, progeny and ability to survive upon exposure to acute oxidative stress were assessed. This study demonstrated that both size particles assayed (M0 and N0), labeled with rhodamine and monitored through fluorescence microscopy, are ingested by the nematode. Moreover, toxicity assays indicated that bare nano-sized particles (N0) have a negative impact on the C. elegans lifespan, reducing mobility and progeny production. By contrast, micro-sized particles (M0) proved innocuous for the nematodes. Furthermore, functionalization of nanoparticles with starch derivative reduced their toxicity in C. elegans. Thus, oral intake of N1 comparatively increased the mean lifespan and activity rates as well as resistance to oxidative stress. The overall findings presented here demonstrate the influence of MSP size and surface on their potential toxicity in vivo and indicate the silica-based mesoporous particles to be a potential support for encapsulation in oral delivery applications. Furthermore, the good correlation obtained between healthy aging variables and viability (mean lifespan) validates the use of C. elegans as a multicellular organism for nanotoxicology studies of MSPs., The authors wish to express their gratitude to the Spanish Government (MINECO Projects AGL2012-39597-C02-01, AGL2012-39597-C02-02, AGL2015-70235-C2-1, MAT2012-38429-C04-01 and MAT2015-64139-C4-1), the Generalitat Valenciana (Project PROMETEOII/2014/047) and Colombian Administrative Department of Science, Technology and Research which supported Ms. Acosta Scholarship. We would also like to thank the Institut de Ciencia dels Materials (ICMUV), the Microscopy Service of the Universitat Politecnica de Valencia and the microscopy service of IATA for technical support. We thank Roquette for the Glucidex samples.

The objective of this work was on the one hand to assess the antibacterial activity of amines anchored to the external surface of mesoporous silica particles against Listeria monocytogenesin comparison with the same dose of free amines as well. It was also our aim to elucidate the mechanism of action of the new antimicrobial device. The suitability of silica nanoparticles to anchor, concentrate and improve the antimicrobial power of polyamines against L. monocytogeneshas been demonstrated in a saline solution and in a food matrix. Moreover, through microscope observations it has been possible to determine that the attractive binding forces between the positive amine corona on the surface of nanoparticles and the negatively charged bacteria membrane provoke a disruption of the cell membrane. The surface concentration of amines on the surface of the nanoparticles is so effective that immobilized‐amines were 100 times more effective in killing L. monocytogenesbacteria than the same amount of free polyamines. This novel approach for the creation of antimicrobial nanodevices opens the possibility to put in value the antimicrobial power of natural molecules that have been discarded because of its low antimicrobial power. Consumers demand for high‐quality products, free from chemical preservatives, with an extended shelf‐life. In this study, a really powerful antimicrobial agent based on a nanomaterial functionalized with a non‐antimicrobial organic molecule was developed as a proof of concept. Following this approach it could be possible to develop a new generation of natural and removable antimicrobials based on their anchoring to functional surfaces for food, agricultural or medical purposes.

The objective of this work was to study salt reduction in the processing and final product of Iberian dry-cured ham manufacturing. For this purpose, high-barrier plastic bags were used in the salting stage, with salt doses of 2.5 and 3.2% at 10 and 15 d. The following aspects were evaluated: the production and salt content of brine, the analytical determinations of the hams after the salting stage, the changes in the total mass of the hams during processing and the analytical and sensory assessment of the dry-cured product. The experiment results showed that the plastic bag salting minimized the production of brine by 61 and 63% and reduced the salt content in the final product without altering the physicochemical characteristics or the hygienic quality of the dry-cured ham. In the sensory analysis, the samples salted with 2.5% doses were preferred by consumers.

The objective of this work was to test the capability of laser-backscattering imaging technique to model changes produced throughout in vitro gastrointestinal digestion of chicken egg white gel as protein matrix model. Evolution of the matrix sample was monitored by analysing protein digestibility, zeta potential, particle size, and imaging every 20 min during the digestion process. Laser-backscattering was based on capturing the diffraction patterns generated by laser-light after being transmitted through matrix samples. Differences in imaging data were observed for the different zones of the studied diffraction patterns. This complexity was solved by a dimensional reduction using multivariate statistics, obtaining R2 >0.90 in calibration studies. Results indicated that imaging device captured the variance produced due to changes in concentrations of protein compounds in despite of changes produced by pH and reagents addition. Therefore, laser-backscattering imaging was capable of monitoring the digestion of egg white gel during gastric and intestinal phases.

[EN] The combination of antifungal agents (cinnamon bark oil, zinc gluconate and trans-ferulic acid) in oil-in-water emulsions to control the fungal spoilage of strawberry jams, minimising essential oil's sensory impact, was evaluated in this work. The in vitro assays of free antifungal agents were performed against five fungal strains; meanwhile, the emulsions assays were conducted against Aspergillus niger given its strong resistance and its relevance in strawberry products. The emulsion formulated with 0.08 mg/g of essential oil was able to inhibit mould growth after the incubation period. The incorporation of zinc gluconate or trans-ferulic acid, independently of the concentration used, allowed to reduce a 25% the amount of essential oil needed to inhibit the microbial growth. The combination of antifungal agents in the emulsions has demonstrated to be an effective alternative to reduce the amount of essential oil employed, maintaining the hygienic quality and sensory profile of the strawberry jam. (C) 2017 Elsevier Ltd. All rights reserved., Author Susana Ribes is grateful to the Universitat Politècnica de València (UPV) for a FPI grant.

Food manufacturers need to reduce sodium content to meet consumer and public health demands. In the present study, the use of sodium-free (SF) salt and KCl to develop a novel smoke-flavoured salmon product with reduced sodium content was evaluated. Fifty percent of NaCl was replaced with 50% of SF salt or 50% KCl in the salmon smoke-flavouring process, which was carried out using water vapour permeable bags.; Results: Triangle tests showed that samples with either SF salt or KCl were statistically similar to the control samples (100% NaCl). Because no sensorial advantage in using SF salt was found compared to KCl and given the lower price of KCl, the KCl-NaCl samples were selected for the next phase. The changes of physicochemical and microbial parameters in smoke-flavoured salmon during 42 days showed that partial replacement of NaCl with KCl did not significantly affect the quality and shelf-life of smoke-flavoured salmon, which was over 42 days.; Conclusion: Smoke-flavoured salmon with 37% sodium reduction was developed without affecting the sensory features and shelf-life. This is an interesting option for reducing the sodium content in such products to help meet the needs set by both health authorities and consumers. © 2017 Society of Chemical Industry.; © 2017 Society of Chemical Industry.

[EN] Essential oils and their main compounds have been studied in-depth for their antifungal properties against a wide variety of microorganisms. However, the strong odour emitted by them, even at low concentrations, makes their incorporation into food matrices difficult. Immobilisation of antimicrobial compounds on solid surfaces could be a strategy to reduce their odour impact. The antifungal effectiveness of eugenol and thymol bioactive agents, free and immobilised on mesoporous silica microparticles (MCM-41 family), and their impact on the final aroma and fungal decay of strawberry jam, were evaluated herein. Free eugenol and thymol exhibited good antifungal properties against the fungi strains tested, and thymol proved more effective. The antifungal activity of immobilised eugenol and thymol displayed greater antifungal activity for immobilised eugenol. The jams prepared with immobilised eugenol on MCM-41 microparticles exhibited no mould and yeast development during the studied storage time. The sensory evaluation confirmed that eugenol and thymol immobilisation reduced their typical strong impact on strawberry jam flavour. This work demonstrates the promising use of immobilised eugenol on mesoporous silica microparticles to control strawberry jam decay. (C) 2017 Elsevier Ltd. All rights reserved., Authors gratefully acknowledge the financial support from MINECO-Spanish Government and FEDER-EU (Projects AGL2012-39597-C02-01, AGL2015-70235-C2-1-R and MAT2015-64139-C4-1) and the Generalitat Valencia (Project PROMETEOII/2014/047). Furthermore, author Susana Ribes is grateful to the Universitat Politecnica de Valencia (UPV) for her FPI grant.

[EN] Four signals configurations were studied, two of them built by small increases of potential and two with bigger increments. The highest current values were obtained when pulses with bigger change of potential were used although the best results were shown by the pulse sequence which included an intermediate pulse before the relevant pulse. A mathematical model based on trolox pattern was developed to predict antioxidant capacity of aliso, employing information obtained from all the electrodes, although model validation could be done only employing the information from gold electrode.

[EN] Variation in methylxanthines (theobromine and caffeine) and flavanols (catechin and epicatechin) was studied in a large set of cocoa powders (covering different origins, processing parameters and alkalisation levels). The content of these compounds was established by high-performance liquid chromatography (HPLC), whose results showed that the alkalisation process lowered the content of all analytes, whose loss was more evident in flavanols. Therefore, the determination of these analytes in a huge set of samples allowed not only better knowledge of the concentration variability in natural commercial cocoas from different origins, but also the understanding of the effect that industrial alkalisation has on these contents. The feasibility of reflectance near-infrared spectroscopy (NIRS) combined with partial least square (PLS) to non-destructively predict these contents, was also evaluated. All the analytes were generally well predicted, with predictions for methylxanthines (R-P(Z) 0.819-0.813 and RMSEP 0.068-0.022%, and bias 0.005 and 0.007 for theobromine and caffeine, respectively) and for flavanols (R-P(Z) 0.830-0.824; RMSEP 8.160-7.430% and bias - 1.440 and -1.034 for catechin and epicatechin, respectively). Thus NIRS could be an alternative fast reliable method for the routine assessment of these analytes in the cocoa industry., The authors would like to acknowledge the financial support of the Spanish Government and European Regional Development Fund (Project RTC-2016-5241-2). M. A. Quelal thanks the Ministry of Higher Education, Science, Technology and Innovation (SENESCYT) of the Republic of Ecuador for her PhD grant. Olam Food Ingredients Company is aknowledged for proving part of the cocoa samples used in the study.

[EN] This study examined Spanish consumer knowledge and perceptions of fat content in minced meat products, as well as the most relevant aspects considered to accept or reject these products. The majority of respondents overestimated the fat content of different minced meat types. Most consumers would not detect fat variations between +/- 2 g fat/100 g. The word association task evidenced different perceptions of minced meat according to both meat types (beef-pork or chicken-turkey) and packaging (on trays, bulk). The colour and appearance of the products were very important for consumers, who did not attach much importance to the presence of additives. Unpackaged beef-pork meat was perceived as more natural, but fattier and less healthy. Chicken-turkey meat was associated with health and low-fat, but also with dislike. This study provides relevant information to develop or reformulate new meat products.

Classifiers are tools widely used nowadays to process data and obtain prediction models that are trained through supervised learning techniques; there is a wide variety of sensors that acquire the data to be processed, such as the voltammetric electronic tongue, as a device employed to analyze food compounds. This paper presents a normal and decaffeinated coffee beverage classifier using a Support Vector Machine with a linear separation function, detailing the classification function and the model optimization method; to train the model, the data measured by 4 electrodes of a voltammetric tongue that is excited by a predetermined sequence of positive pulses is used. In addition, the results graphically show the measurements obtained, the support vectors and the evaluation data, the values of the classifier parameters are also presented. Finally, the conclusions establish an acceptable error in the classification of coffee drinks according to caffeine presence at the sample analyzed.

[EN] Available disinfection methods and therapies against Helicobacter pylori have multiple disadvantages, such as increased prevalence of antibiotic-resistant strains, which requires the search for novel effective antimicrobial agents against H. pylori. Among them, naturally-occurring antimicrobial compounds, like essential oil components (EOCs), have been reported as substances with anti-H. pylori potential. To avoid the disadvantages associated with using EOCs in their free form, including volatility, low water solubility and intense sensory properties, their immobilisation in inert supports has recently been developed. This study sought to evaluate the inhibitory properties of EOCs immobilised on silica microparticles against H. pylori and to elucidate the mechanism of action of the immobilised antimicrobials. After the preparation and characterisation of the antimicrobial supports, the susceptibility of H. pylori in the presence of the immobilised compounds was assessed by plate count, fluorescent viability staining and direct viable count-fluorescent in situ hybridisation analyses. The antimicrobial supports were found to inhibit H. pylori growth, and to induce morphological and metabolic alterations to the H. pylori membrane, with a minimum bactericidal concentration value between 25 and 50 mu g/ml according to the tested EOC. These findings indicate that immobilised EOCs can be used as potential antimicrobial agents for H. pylori clearance and treatment., Authors gratefully acknowledge the financial support from the Ministerio de Ciencia, Innovacion y Universidades, the Agencia Estatal de Investigacion and FEDER-EU (Project RTI2018-101599-B-C21). M.R.R. acknowledges the Generalitat Valenciana for their Postdoctoral Fellowship (APOSTD/2019/118).