Search

This work aimed to propose a methodology to be used as a fast screening method to detect adulteration in oil capsules using Near Infrared (NIR) spectroscopy through Principal Components Analysis (PCA). The experiment consisted in measuring the NIR spectra from 25 different intact oil capsules from different oil/mixtures and, to provide a trustworthy comparison, the oil capsule internal content was extracted to be evaluated by High-Resolution Gas Chromatography (HRGC). In order to be useful, the proposed methodology demands for a known certified set of samples to be used as a target. The ability to detect adulteration was verified comparing between NIR and GC PCA scores disposal, in which 6 samples did not match. Therefore, the methodology suggests that these 6 samples would be evaluated by HRGC in place of the whole set of 25 samples. Thus, NIR spectroscopy could be used as a fast screening method to indicate which samples should be analyzed by gas chromatography, considering that each coinciding sample, i.e. disposed of in agreement to the HRGC PCA score, is already certified by HRGC regarding on their content.

There is an increasing demand for healthier foodstuff containing specific compounds such as Polyunsaturated Fatty Acids (PUFAs). In the case of PUFAs, protection against oxidative degradation is challengeable and microencapsulation emerges as an alternative. Mayonnaises containing microencapsulated oils could be a source of PUFAs. The objective was to formulate mayonnaises containing microencapsulated chia seeds oil, pumpkin seeds oil or baru oil. Micrometric particles with high encapsulation efficiency were produced and thermal analyses indicated an increased thermal stability of all oils after encapsulation. Rheology studies highlighted an increase in the mayonnaise viscosity when microparticles containing chia and pumpkin seeds oil were added. Mechanical texture was not affected by the presence of microparticles in the mayonnaise in all formulations tested. Nevertheless, samples containing microcapsules up to 5%wt were not distinguished from the base-mayonnaise in the sensorial test. Overall, enriched mayonnaises were successfully produced and encapsulation was efficient in protecting oils from oxidation. Authors thank CAPES , CNPq and Fundação Araucária for the support. The authors are grateful to the Foundation for Science and Technology ( FCT , Portugal) and FEDER under Programme PT2020 for financial support to CIMO (UID/AGR/00690/2013) and L. Barros contract. info:eu-repo/semantics/publishedVersion

Compact nuclear magnetic resonance (NMR) spectroscopy combined with chemometric tools opens new perspectives for NMR use. This work compares the potential of 43, 60 and 400 MHz NMR spectroscopy for quality control of edible oils. Partial least squares regression (PLSR) and support vector regression (SVR) models built on the three NMR devices had equivalent performances for fatty acids and iodine value, and the models built with the low field spectra were equivalent to the high field. Moreover, performances for calibration indicated that most of the models built with medium/or high-resolution fields presented reproducibility values lower than the minimum accepted by the American Oil Chemists' Society (AOCS). Compared to classical methods, this new approach allows the application of medium resolution devices as a sample screening tool in analytical laboratories since it allows the spectrum obtention in a few seconds, without the need for sample preparation or the use of deuterated solvents.

Partial substitution of margarine by microencapsulated chia oil (rich in n-3 and n-6 fatty acids) in carnauba wax solid lipid microparticles was investigated, to obtain cookies containing omega-3 and omega-6. The microparticles were prepared by the hot homogenisation in which the lipid phase is molten and dispersed as small droplets in an aqueous phase followed by a cooling/solidification step. Cookies were produced using only margarine (control) and also with partial substitution of margarine by microencapsulated chia oil (15% and 30%wt). Texture profile analysis results of the cookie dough (pre-baking) were affected (p

The hydrogenation process of soybean oil is monitored through time-consuming methodologies that demand sample preparation and produce chemical residues. Thus, it is necessary to develop faster low-cost waste-free instrumentation methodologies. The aim of this work was to evaluate an ultra-compact near-infrared spectrometer in tandem with the partial least squares regression (PLSR) or support vector regression (SVR) in the control of the hydrogenation process. Models were used to predict the saturated fatty acids (SFA), unsaturated fatty acids (UFA), monounsaturated fatty acids (MUFA), trans fatty acids (TFA), polyunsaturated fatty acids (PUFA), and the iodine value (IV). The values predicted by the PLSR and SVR models were compared to the experimental values obtained by gas chromatography. A methodology for feature selection was also assessed, which was able to reduce by up to 85% the variables used in the models without loss of performance. The values obtained for root mean square error of cross validation, root mean square error of calibration, root mean square error of prediction, and r 2 remained very close for both PLSR and SVR. Regarding RSD, all values were above 5% for the PLSR models, whereas for the SVR, the RSD presented values lower than 5% for IV and UFA. It is worth noting that the spectrometer used has low cost, effortless assembly, and easy handling, which allows its use in any environment. Through the results obtained, it was demonstrated that the ultra-compact NIRS spectrometer in tandem with PLSR or SVR represent an alternative to monitor the industrial hydrogenation process of soybean oil.

The industrial hydrogenation of soybean oil is well established. However, its control is carried out through time-consuming methods. The objective of this study was to evaluate the mid-infrared spectroscopy (FTIR-ATR) in tandem with support vector machines (SVM) in controlling the hydrogenation process. Models were constructed to predict the content of saturated fatty acids (SFA), unsaturated fatty acids (UFA), monounsaturated fatty acids (MUFA), trans fatty acids (TFA), polyunsaturated fatty acids (PUFA) and the iodine value (IV). The values predicted by the SVM models were compared to values obtained through gas chromatography. Feasible multivariate models were obtained with r 2 minimum of 0.96 and RMSEP in the range of 0.65–2.65. Feature selection using correlation spectra was also efficient, maintaining the performance of the models and reducing the number of variables used by up to 94%. Therefore, it was demonstrated that FTIR-ATR methodology with SVM could be applied to monitor industrial hydrogenation.

The stability of tilapia croquette mixtures was evaluated for 240 days, through analyses of water activity (aw), lipid oxidation (TBARS) and sensory and microbiological assays. The control mixture was composed of tilapia mince, wheat and rye flours and seasonings while the enriched mixture also contained flaxseed flour. Aw increased significantly over time, from 0.1666 to 0.5392 for the control mixture and from 0.0554 to 0.5415 for the enriched mixture. TBARS values increased from 0.08 to 0.38 mg kg−1 for the control mixture and from 0.11 to 0.40 mg kg−1 malondialdehyde (MDA) for the enriched mixture. Appearance, texture and overall acceptance of the control mixture remained constant and the flavour improved during storage, while sensory attributes of the enriched mixture did not change. Overall acceptance was nearly 8 for the control mixture and 6 for the enriched mixture using a 9-point hedonic scale, where 9 = ‘like a lot’ and 1 = ‘dislike intensely’. Microbiological parameters did not exceed the legal...

Whey protein supplements (WPS) intake has been increasing worldwide as they are mainly used to improve overall athletic performance. Adding other bioactives such as polyunsaturated fatty acids (PUFA) may be an alternative to help fulfill nutritional needs. Microencapsulation is able to protect PUFA-rich oils from oxidation, but important aspects of particle production and their influence on food properties must be evaluated. This study aimed to develop WPS with microencapsulated green coffee and walnut oils using stearic acid as a wall material. Oxidative stability (differential scanning calorimetry) of the oils increased (from 82 ± 4 to 110 ± 10 kJ mol−1 for green coffee oil and from 90 ± 5 to 149 ± 1 kJ mol−1 for walnut oil) after encapsulation and WPS rheological properties were not affected by the microcapsules (p 0.05). Sensory analysis of the supplement containing microencapsulated green coffee oil showed a lower sensory preference than the blank sample, but no difference was found with the blank sample in the case of walnut oil (p 0.05). The encapsulation strategy used to produce an enriched WPS was efficient in protecting the oils from oxidative degradation. This study was financed in part by the Coordenaç~ao de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES) - Finance Code 001. This work was financially supported by Associate Laboratory LSRE-LCM (UIDB/50020/2020) and CIMO (UIDB/00690/2020) funded by national funds through FCT/MCTES. info:eu-repo/semantics/publishedVersion

Chia is a good source of fibre, protein and antioxidants, and is also rich in polyunsaturated fatty acids, particularly α-linolenic acid (18:3 n-3). This fact makes it increasingly interesting for studies of its composition and nutritional quality, because it may be useful for inclusion in diets or in novel food formulations. The objective of this study was to determine the chemical and fatty acid composition and the indices of nutritional quality of the lipid fraction of chia seed produced in Brazil. In respect to chemical composition, an average grade of 8.14% moisture, 20.11% protein, 27.72% lipid and 3.94% ash was detected. Sixteen fatty acids were quantified in the chia, highlighting the prevalence of polyunsaturated fatty acids, mainly 18:3 n-3. All indices of nutritional quality of lipid fraction assessed (Hypocholesterolaemic/ hypercholesterolaemic FA ratio, atherogenic index and thrombogenic index) indicated that chia has a high lipid fraction quality and its inclusion in diet or as an ingredient in food products can be an ally in the reduction of cardiovascular problems.

Encapsulation of poly-unsaturated fatty acid (PUFA)is an alternative to increase its stability during processing and storage. Chia (Salvia hispanica L.) oil is a reliable source of both omega-3 and omega-6 and its encapsulation must be better evaluated as an effort to increase the number of foodstuffs containing PUFAs to consumers. In this work chia oil was extracted and encapsulated in stearic acid microparticles by the hot homogenization technique. UV-Vis spectroscopy coupled with Multivariate Curve Resolution with Alternating Least-Squares methodology demonstrated that no oil degradation or tocopherol loss occurred during heating. After lyophilization, the fatty acids profile of the oil-loaded microparticles was determined by gas chromatography and compared to in natura oil. Both omega-3 and omega-6 were effectively encapsulated, keeping the same omega-3:omega-6 ratio presented in the in natura oil. Calorimetric analysis confirmed that encapsulation improved the thermal stability of the chia oil.

Although its high protein quality, Nile tilapia mince is low in essential fatty acids. This research evaluated the effect of the addition of flaxseed flour to sensory acceptance and nutritional status of Nile tilapia croquettes. The basic formulation of tilapia croquette was enriched with different contents of flaxseed flour, and a ranking preference test was used to determine which formulation did not differ from the basic product. Proximate and fatty acids compositions and nutritional quality indices of lipids of raw and deep fat fried formulations were determined. The ranking preference test indicated that the limit of addition of flaxseed flour is 12.5 g 100 g−1. In addition to the enhanced content of omega-3, the enriched formulation showed a lower loss of this substance during frying and better indices of nutritional quality of lipid than the basic product. The enrichment of croquettes with flaxseed flour significantly improved the nutritional value, even though they had been subjected to deep fat frying.

The aim of this work was to analyze the fatty acid and proximate composition of five brands of breaded chicken steak (A, B, C, D, and E) by accurate chromatographic quantification and to compare the experimental results with food label nutrition facts. The protein values of all brands were in agreement with the Brazilian regulation values, except for that of sample E, which presented the highest lipid content. Thirteen fatty acids were identified in the studied brands and the major ones were oleic acid, linoleic acid, and palmitic acid. The polyunsaturated fatty acid/saturated fatty acid ratios were within the values considered appropriate for human health; however, the high n-6/n-3 ratios found can result in an unbalanced intake of these fat acids. Only samples D and E can be considered trans free according to the regulations. The comparison of the analyses' results and the food label nutrition facts showed little variation in protein values. Nevertheless, most brands underestimated their lipid and energy levels. Brand B and C labels declared "free of trans", but the obteined results showed levels excedding those especified by regulation to be considered trans free values. O objetivo deste estudo foi analisar a composição centesimal e de ácidos graxos de cinco marcas de steak empanado de frango (A, B, C, D e E). As análises de ácidos graxos foram realizadas por cromatografia gasosa e técnicas de quantificação absoluta. Os resultados experimentais foram comparados com valores constantes nos rótulos. Os valores encontrados para proteína de todas as marcas estavam em acordo com o estabelecido pela legislação brasileira, exceto o da amostra E, a qual apresentou o maior teor lipídico. Treze ácidos graxos foram identificados nas marcas avaliadas, sendo os majoritários os ácidos: oleico, linoleico e palmítico. As razões dos ácidos graxos poli-insaturados/ácidos graxos saturados encontraram-se dentro dos valores considerados adequados para a saúde humana, porém, as elevadas razões n-6/n-3 encontradas podem resultar em um desequilíbrio na ingestão destes ácidos graxos. Apenas amostras D e E podem ser consideradas livres de trans de acordo com a legislação vigente. A comparação entre os resultados das análises e os valores constantes nos rótulos apresentaram pequenas variações nos teores de proteína, entretanto, a maioria das marcas subestimou os teores de lipídios e valor energético. Os rótulos das marcas B e C declaravam-se livre de trans, entretanto os resultados obtidos apontam teores acima dos valores permitidos pela legislação para serem consideradas livre de trans.

Encapsulation of poly unsaturated fatty acid (PUFA) is known to be an alternative to increase its stability during processing and storage. Chia (Salvia hispanica L.) oil has raised interest as a reliable source of both omega-3 and omega-6 but its encapsulation must be better evaluated. In this work, chia oil was extracted and encapsulated in stearic acid microparticles by the hot homogenization technique. UV-Vis spectroscopy coupled with Multivariate Curve Resolution with Alternating Least-Squares methodology demonstrated that no oil degradation or tocopherol loss was expected to occur during the encapsulation procedure. After lyophilization, the fat acids profile of the oil loaded microparticles was determined by gas chromatography and compared to that of the in natura oil. Both omega-3 and omega-6 were effectively encapsulated keeping the same omega-3:omega-6 ratio presented in the in natura oil.

The aim of this work was to elaborate a skimmed symbiotic yoghurt, using starter culture (Lactobacillus bulgaricus and Streptococcus thermophillus), Lactobacillus casei as probiotic microorganism and inulin and oligofructose as prebiotic ingredients. The probiotics characteristics (acid and bile resistance) of L. casei and the number of lactic acid bacterias in the product had been tested, as well as the physicochemical characteristics of the yoghurt (pH, acidity, chemical composition and viscosity). Acceptance tests had been carried out with the symbiotic yoghurt added with strawberry pulp and flavour, and two different types of sweetening agents. The yoghurt supplemented with prebiotics presented pH 4.33, acidity of 1.15% and amount of lactic acid bacteria superior to the minimum necessary to characterize it as probiotic. L. casei showed resistance to acid and bile, confirming important probiotics characteristics. The prebiotic yoghurt presented higher viscosity than the not supplemented one. There was no significant difference between the acceptance (above 80%) of yoghurts sweetened with the two types of sweetening agents.

Food industry is increasingly concerned about their role in environmental responsibility. Recycling of meat package is a challenge since the presence of residual lipids limit the amount of recycled material that could be added to the pure material. In this work the efficiency of an enzymatic detergent in removing total lipids residues from discharged meat polyethylene package was evaluated. The experimental parameters were the enzymatic detergent concentration, temperature and the mass of package used during the detergent application. Soxhlet extraction (3 hours, 40 ºC,) was used to determine the amount of total lipids present in the package both before and after the use of the detergent. The solvent used was petroleum ether and the amount of total lipids was determined gravimetrically. The polyethylene meat package presented an initial amount of total lipids of (15.7± 0.7) %. Results demonstrated that the efficiency increased with the increase in temperature and detergent concentration as well as with the decrease in the mass of the polyethylene sample. Any decrease in the enzymatic activity was observed for the evaluated temperatures. Also there was a limit in the amount of polyethylene package that could be used probably because greater amounts of sample hindered stirring and homogenization. According to the experimental design the maximum efficiency is expected to be 81.72% when the following conditions are used: 54°C, enzymatic detergent concentration of 19g/L and a package sample amount of 4 grams.DOI: 10.14685/rebrapa.v5i3.178

In recent years several researchers have conducted studies comparing total lipids extraction methods, to find the most efficient method. The objective of this work was to study four different total lipids extraction methods in soybean crumbs and chicken thigh hillbilly with solvents of different degrees of toxicity and polarity (n-hexane, n-hexane-isopropanol, chloroform, methanol and ethanol). The study showed that the Soxhlet method, using ethanol as solvent was more efficient in the total lipids extraction present in soybean crumbs (5.38%), but not significantly different (p ≤ 0.05) for organic chicken thigh (3.35%), among the methods. The Bligh & Dyer cold method was the most efficient for the soybean crumbs.DOI: http://dx.doi.org/10.14685/rebrapa.v1i2.19

Antioxidants are substances that react with free radicals stabilizing and preventing their harmful actions to the organism and are present in a wide variety of foods and beverages. Due to importance of antioxidant activity in the some foods, several analytical methods have been proposed among them include FRAP, ORAC, total polyphenol content and DPPH methods. The main objective of this study is to propose an analytical methodology using a flow injection analysis system (FIA), with a merging zones configuration, for determination of total antioxidant activity by DPPH radical scavenging assay. The FIA system conditions were optimized with the response surface methodology using the central composite rotatable design. The optimization parameters studied were: the carrier flow rate, the lengths of the sample and reagent loops and the length of the reactor. According to the results, levels of selected parameters were: carrier flow rate 1.12 mL min-1, length of the loops 18.5 cm and length of the reactor 234.6 cm. The detection and quantification limits were, respectively, 2.647 and 8.824 μ mol L-1 acid galic / mL wine. The proposed method had an analytical frequency of 41 samples per hour and a 58% saving in the consumption of reagent DPPH and 62.6% in the consumption of carrier agent methanol compared to the conventional method. The DPPH assay adapted to the FIA system under the optimization conditions was utilized to determine the antioxidant activity of wine samples. Os antioxidantes são substâncias que reagem com os radicais livres estabilizando e impedindo suas ações maléficas ao organismo e estão presentes em uma grande variedade de alimentos e bebidas. Devido à importância da atividade antioxidante em alimentos, vários métodos analíticos têm sido propostos, dentre os quais incluem o método FRAP, ORAC, Fenólicos Totais e o DPPH. O objetivo principal do trabalho foi propor uma metodologia analítica utilizando um sistema de análise por injeção em fluxo (FIA), com configuração de zonas coalescentes, para determinação da atividade antioxidante total por captura do radical DPPH. As condições do sistema FIA foram otimizadas através da metodologia de superfície de resposta usando um planejamento fatorial composto central rodável (PFCCR). Os parâmetros de otimização estudados foram: fluxo do transportador, comprimento das alças de amostragem e do reagente e comprimento do reator. De acordo com os resultados, os níveis dos parâmetros selecionados foram: fluxo de 1,12 mL min-1, comprimento das alças de 18,5 cm e comprimento do reator de 234,6 cm. Os limites de detecção e quantificação foram 2,647.10-6 e 8,824.10-6 mol L-1 ácido gálico / mL de vinho. O método proposto apresentou freqüência analítica de 41 análises por hora e uma economia de 58% no consumo do reagente DPPH e 62,60% no consumo do agente transportador metanol em comparação com o método convencional. O ensaio DPPH adaptado ao sistema FIA de zonas coalescentes, nas condições otimizadas foi utilizado para determinar a atividade antioxidante total de amostras de vinho. [7] viii, 57 f

Perilla frutescens (perilla) is a plant grown and consumed in several Asian countries, whose seeds are rich in lipids and proteins. The major fatty acid present in the total lipids of perilla is alpha-linolenic acid, which is an essential fatty acid to the human body, belonging to the omega-3 family. Benefits related to the consumption of alpha-linolenic acid correspond to the evolution of brain activity and nervous system, suppression of carcinogenesis, metastasis, thrombosis, and allergic reactions. The optimal dose of fatty acids ômega-6/omega-3 should range between 1:1 to 4:1, depending on the health condition. It is essential to reduce the intake of omega-6 to prevent and monitor chronic diseases, therefore, the balance of omega-6 and omega-3 is very important for human development and homeostasis. The potential intake of omega-3 depends on the presence of these in popular products such as bread. This paper will evaluate the physical and chemical characteristics and fatty acids compostion of this type of bread made with wholemeal perilla, emphasizing omega- 3 fatty acids contents. (...). The replacement of wheat flour by wholemeal perilla in bread developing promoted changes in chemical composition, mainly on the content of total lipids. There were significant changes in fatty acid composition between the formulations, especially in the content of saturated fatty acids, polyunsaturated, omega-6 and omega-3. Was observed significantly increase on the levels of omega- 3 fatty acid in formulations with wholemeal perilla, decrease on the levels of omega-6 fatty acids and reducing the values of ratio n-6/n-3, making products more nutritious for human consumption . The addition of perilla in the form of wholemeal did not cause significant increase in phenolic compounds and antioxidant properties in the final products. The formulation with substitution of wheat flour at 1% showed the better acceptability index and the higher frequency of favorable responses to purchase intent. This formulation did not differ from the standard in sensory attributes, instrumental color and possessed amount of omega-3 enough to supply 5.63 and 8.19% of the American recommended daily intake of alpha-linolenic acid, for adult male and adult female, respectively. Perilla frutescens (perilla) é uma planta cultivada e consumida em diversos países asiáticos, cujas sementes são ricas em lipídios e proteínas. O principal ácido graxo presente nos lipídios totais da perila é o ácido alfa-linolênico, que é um ácido graxo essencial ao organismo humano e pertencente à família ômega-3. Os benefícios relacionados ao consumo de ácido alfa-linolênico correspondem à evolução da atividade cerebral e do sistema nervoso, supressão da carcinogênese, metástase, trombose e reações alérgicas. A dose ideal de ácidos graxos ômega-6/ômega-3 deve variar entre 1:1 a 4:1, dependendo do estado de saúde. É essencial reduzir a ingestão de ômega-6 para prevenção e monitoramento de doenças crônicas, portanto, o balanço de ácidos graxos ômega-6 e ômega-3 é muito importante para homeostase e desenvolvimento humano. A ingestão potencial de ácidos graxos ômega-3 depende da presença destes em produtos populares, como o pão de forma. Este trabalho abordará a caracterização físico-química e de ácidos graxos deste tipo de pão formulado com a farinha integral de perila, com ênfase em ácidos graxos ômega-3. (...). A substituição de farinha de trigo por farinha integral de perila na elaboração de pão de forma promoveu mudanças na composição centesimal, principalmente quanto ao teor de lipídios totais. Houve mudança significativa na composição em ácidos graxos entre as formulações, especialmente no teor de ácidos graxos saturados, poliinsaturados, ômega-6 e ômega-3. Foi observado aumento significativo do teor de ácido graxo ômega-3 nas formulações com farinha integral de perila e diminuição dos níveis de ácidos graxos ômega-6 e, portanto, redução dos valores da razão n-6/n-3, tornando os produtos mais nutritivos para o consumo humano. A adição de perila, na forma de farinha integral, não promoveu aumento significativo de compostos fenólicos e de propriedades antioxidantes nos produtos finais. A formulação com substituição da farinha de trigo em 1% apresentou melhor índice de aceitabilidade e maior freqüência de respostas favoráveis quanto à intenção de compra. Tal formulação não diferiu da padrão nos quesitos sensoriais e de cor instrumental e possuiu quantidade de ácidos graxos ômega-3 capaz de suprir 5,63 e 8,19% da ingestão diária recomendada americana de ácido alfa-linolênico, para homens e mulheres adultos, respectivamente. 41 f