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This study aimed to optimize the extraction solvents for Bordo grape (Vitis labrusca) seeds by response surface methodology regarding to the antioxidant activity (AA) and trans-resveratrol content. Fatty acids (FA) and AA of the oil obtained by pressing cold method were also determined. The extraction optimization was determined by the statistical simplex-centroid mixing scheme, enabling the analysis of solvents effects (water, ethanol and acetone) and their mixtures on the responses. AA was performed by DPPH, ABTS and FRAP methods, and by total phenolic compounds and flavonoids. FA were determined by GC and trans-resveratrol by HPLC. The extracts containing ternary fraction of solvents showed greater AA, increasing about 20 times compared to pure solvent. The composition that showed the best response ranged between 45-48% of water, 14-20% of ethanol and 35-38% of acetone for both grape seeds, with polarity ranged from 0.705 to 0.706. The oil from seeds showed high concentrations of PUFA, particularly linoleic acid. The optimized extraction method improved the use of this residue as a potential antioxidant source for food industry.

The aim of this study was to produce cereal bars (CB) added with tempeh flour (TF) and evaluate the nutritional composition, fatty acids profile, isoflavone content and sensory acceptance. Tempeh was produced from organic soya beans cotyledons fermented by Rhizophus oligosporus followed by freeze-drying and milling in order to obtain the TF. The addition of 10%, 15% and 20% TF to CB resulted in both protein and lipid content increase and a higher polyunsaturated/saturated fatty acids ratio. The content of isoflavone aglycones, the forms considered to have higher biological activity, was higher in TF than in soya bean, which was also reflected in the CB chemical composition. An acceptance test showed that CB added with TF (up to 15%) were sensory accepted. Overall results suggest that the addition of TF as an ingredient in cereal bars allows improving the chemical and functional characteristics of this type of ready-to-eat foods. info:eu-repo/semantics/publishedVersion

The olive oil consumption has spread worldwide, increasing the necessity of quality assessment, and so forth, the search for new, alternative, and rapid data interpretation has started, boosting the interest and the use of data fusion that seek for an integration of results from different techniques or methodologies for the same data set. To better understand the storage effects on the Brazilian monovarietal extra virgin olive oil, data fusion was applied in the classical and alternative analysis, highlighting the similarities and differences between the techniques, assisting in the result interpretation. This perspective and strategy bring development to food chemistry analysis.

This work aimed to investigate and compare the composition and the physicochemical properties of 18 different sources of edible vegetable oils. A systematic study on the correlation between composition and physical properties was performed using Fourier Transform Infrared (FTIR) Spectroscopy and fatty acid chromatographic analysis. Principal component analysis of FTIR spectra is performed to classify edible oils concerning their physical properties. The results demonstrate the potentiality of the method associated with multivariate statistics analysis as powerful, fast, and non-destructive tools for characterization and quality control of edible vegetable oils.

The influence of stunning methods on the physicochemical and biochemical parameters of chicken breast meat, as indicators of bird stress, was investigated. A total of 200 Cobb broiler chickens aged from 42 to 48 d were submitted to gas or electrical stunning and slaughtered according to the standard industry practice. Pectoralis major muscles (24 h post-mortem) from broilers stunned by electronarcosis exhibited a higher L* and R-value and lower pH45min than did those from gas stunning, indicating modification of the glycolytic rate. Protease activity, measured as the myofibril fragmentation index, and the sarcoplasmic Ca2+ concentration were highest in samples from broilers stunned by electronarcosis, suggesting the greatest activity of the calpain system. In the fatty acid profile, a higher ratio of polyunsaturated fatty acids was observed in samples from broilers stunned by electronarcosis. These characteristics are related to phospholipase A2 activity, which is higher in animal stress conditions. These results indicated that the gas-stunning method produced less bird stress than electrical stunning.

El objetivo de este estudio es evaluar el efecto de diferentes aceites (soja, girasol, canola y pollo) en el alimento para pollos, creados para el rendimiento de los pollos de engorde. Se analizaron los contenidos de perfil de ácidos grasos, colesterol en carne de pollo y sus respectivos rendimientos como pollos de engorde. Los 1,000 machos de pollos de engorde de Cobb de 42 días de vida, solo fueron alimentados con una dieta específica, y después de este período fueron sacrificados. Los pollos utilizados como control se sacrificaron a los 21 días de edad, estos pollos se alimentaron a base de una dieta comercial. Se informa que el rendimiento del pollo de engorde, el contenido de colesterol y la composición fisicoquímica de la alimentación en los cortes de carne (pechuga sin piel, piel de la pechuga y muslo sin piel) se ven afectados por la alimentación específica. El perfil de ácidos grasos de la dieta varió dependiendo de cada aceite utilizado en la formulación, encontrándosevalores más bajos de ácidos grasos saturados (SFA) para los aceites de canola y girasol. En la carne de pollo, los resultados para el muslo sin piel, la pechuga sin piel y la piel de la pechuga fueron similares a los perfiles de ácidos grasos, variando solo el tipo de tratamiento de alimentación. Después del análisis de las muestras, los ácidos grasos poliinsaturados (PUFA), que aparecen en mayor concentración, son 18: 2n-6 y 18: 3n-3. Por lo tanto, los cortes de pollos alimentados con aceites de girasol y soja evidenciaron niveles más altos de 18: 2n-6. Variablemente, los cortes de pollo alimentados con aceite de canola, mostraron niveles más altos de 18: 3n-3, en comparación con otros tratamientos. Considerando el equilibrio de n-6 / n-3 y la concentración de ácido graso insaturado en la carne de pollo, los pollos alimentados con aceite de canola presentaron mejores características nutricionales.

Recent studies on laser induced thermal lens effect has made it possible to use this tool to investigate thermo-physical and chemical properties of biofuels. During laser illumination, a number of light induced effects may take place in the excited volume of the sample. However, the complexity of information included in the thermal lens transients could lead to misinterpretation of the results. This work examines the theoretical and experimental aspects that must be considered when performing biodiesel analysis using thermal lens spectrometry. The induction of photochemical reaction and thermal diffusion processes is carefully accounted for by describing the localized optical path change due to the concentration gradient created within the sample. We characterize mechanical, chemical and photochemical properties of thermal degraded biodiesels, enabling quantitative access of mass diffusion coefficient, photobleaching cross-section, and thermal yield. Dynamic viscosity analysis corroborates the results obtained by thermal lens, describing the method as very sensitive to thermal stability discrimination of biodiesel.

The extra virgin olive oil (EVOO) has a certain oxidation resistance when compared to other vegetable oils without refining process, due to their large composition of monounsaturated fatty acids, antioxidants, and bio-compounds. The main of this research was to evaluate and monitor the behavior of autoxidative processes through the storage time in two packaging systems of different EVOO monovarietals produced in Minas Gerais, Brazil by using ultraviolet and visible spectroscopy (UV–Vis) with multivariate curve resolution with alternating least squares (MCR–ALS). We analyzed six EVOOs produced from different monovarietals (Arbequina, Empeltre, Coratina, Grappolo, Koroneiki, and Maria da Fe), over the course of 1 year, performed the analysis in times 0, 30, 90, 180, and 365 days, and storage in glass bottles and tinplate cans. The UV–Vis spectroscopy coupled with MCR–ALS was a feasible tool to monitor autoxidation processes in EVOO through storage time and in the monitoring of the EVOO quality in different package systems. The glass bottles were a package system that provides more protection for the autoxidation processes with the time for the EVOO from monovarietals Empeltre, Arbequina, and Coratina. In addition, it was possible to make a differentiation between the monovarietal olive oils produced in Brazil by observing the amount of phenolic compounds present in the chemical composition of each oil. Allowing gather information about the formation of oxidative products may correlate with the shelf life of the EVOO.

Biodiesel susceptibility to oxidation is one of the major problems concerning its use as an alternative to diesel fuel. Although well-characterized, the oxidation process cannot be completely prevented since it can be affected by a large number of factors, such as fuel composition, storage conditions, contaminants, temperature, and the presence of air and light. In this work, we propose Fourier transform infrared spectroscopy (FTIR) in association with principal components analysis (PCA) and hierarchical cluster analysis (HCA) as a method for monitoring the extent of oxidation degree of biodiesel in the low rate phase, before the end of the induction period, in which the changes in the physical properties such as viscosity, mass density, and chain composition of the sample remain almost undetectable. A detailed investigation of thermo-oxidation of biodiesel is reported for a mixture of 50/50 (%) of soybean oil and animal fat biodiesels. The biodiesel degradation was accelerated when maintaining the temper...

Eugenol, an essential oil which has antioxidant and antimicrobial properties, has a limited applicability due the high volatility; in this scenario, microencapsulation is a technology that protects the substances from the environment with a physical barrier. This work aims to study the combination of the bovine serum albumin and rice bran protein with carrageenan as encapsulating agents, observing the encapsulation efficiency on eugenol. The spray drying process was used for encapsulation. The process was characterized by thermal and spectroscopy analysis that shows the presence of eugenol encapsulated. Determined by UHPLC and TG, encapsulation efficiency of eugenol was up to 79.4%.

Partially hydrogenated soybean oil and palm olein are oils that are widely used in the food industry. Continuous contact with air may cause changes of the triglycerides chemical structure, to eventually produce substances of lower molar masses that may be toxic to mammals. This study aimed to determine the kinetic parameters for the thermal oxidation of these oils and of their residual used oils from the pre-frying industrial step on preparing breaded chicken meat. The main reactions were followed by thermogravimetry (TG) and differential scanning calorimetry (DSC); the formation of the produced substances was monitored by gas chromatography flame ionization detector (GC-FID) and Fourier transform infrared spectroscopy (FTIR). These analyses indicated different chemical pathways, according to the type of unsaturation and changes in the molecular structures of the fatty acids in the oils. From the thermal analysis, more than one decomposition event was observed during the thermal oxidation process. As the soybean oil has a lower oxidation onset temperature than palm olein, it has lower rate of mass loss, with a higher activation energy value.

This study evaluated the prednisone removal from aqueous solutions using adsorption by an activated carbon of vegetal origin (VAC). A central composite rotatable design (CCRD) and the response surface methodology (RSM) were used to verify the influence of the parameters: pH, adsorbent dose and prednisone concentration in a batch adsorption process. Among the analyzed parameters, only the adsorbent dose and the prednisone concentration were statistically significant (α = 0.05) and the critical values obtained were adsorbent dose: 1.87 g/L, pH 7.56 and prednisone concentration: 3.66 mg/L with 77.51% of prednisone removal by VAC. The kinetic study of the adsorption of prednisone reached the equilibrium in 4 h. The pseudo-first-order model described adequately the kinetics data behavior. The equilibrium experimental data obtained at different temperatures showed that the VAC has a maximum adsorption capacity of 18.04 mg/g at a temperature of 30 °C. The prednisone removal decreased by the increasing temperature and the Langmuir isotherm well described the experimental data (R² > 0.98). Thermodynamic results shown that the prednisone removal of aqueous solutions by VAC is spontaneous and favorable process.

Celiac disease is defined as intolerance to the gluten proteins present in certain cereals used to prepare foodstuffs. We developed and performed physico-chemical, sensory, and nutritional assessments of three formulations of gluten-free cookies containing Linum usitatissimum L. and different levels of whole Chenopodium quinoa BRS Piabiru flour. No gluten was detected in the prepared cookie formulations. The crude protein and total lipid contents ranged from 85.58 to 97.55 and 121.69 to 166.19 g per kg of sample, respectively. The polyunsaturated/saturated and n-6:n-3 fatty acid ratios ranged from 0.85:1 to 0.92:1 and 3.08:1 to 4.38:1, respectively. Formulation C had the best alpha-linolenic acid content, lipid fraction nutritional indices and mineral content per portion, with excellent sensory characteristics. Multivariate analysis highlighted the effect of the concentration of quinoa on the nutritional and sensory qualities of the product. A doença celíaca é definida como a intolerância às proteínas do glúten presente em certos cereais usados na produção de alimentos. Três formulações de biscoitos sem glúten, contendo Linum usitatissimum L. e diferentes concentrações de Chenopodium quinoa BRS Piabiru, foram desenvolvidos e avaliados em relação as caracterísiticas fisico-químicas, nutricionais e sensoriais. Não foi detectado glúten nos biscoitos formulados. O conteúdo de proteína bruta e lipídios totais variaram 85,58 a 97,55 e 121,69 a 166,19 g por kg de amostra, respectivamente. A variação da razão entre os ácidos graxos n-6:n-3 e poliinsaturados/saturados foi de 0.85:1 a 0.92:1 e 3.08:1 a 4.38:1, respectivamente. A Formulação C apresentou melhores teores de ácido alfa-linolênico, índices nutricionais da fração lipídica e conteúdo mineral por porção, com excelentes características sensoriais. A análise multivariada destacou o efeito da concentração de quinoa nas qualidades nutricionais e sensoriais do produto.