ABSTRACT
A microwave-assisted digestion procedure using diluted HNO3 and H2O2 was developed for multi-element determination in guarana samples by ICP OES. Optimization step was performed employing a mixture design with pseudocomponents using HNO3, H2O2 and H2O. The analytical signal of each element, residual acidity and residual carbon content were optimized simultaneously using the desirability function. The best condition for digestion of a 250â¯mg sample mass resulted from a mixture constituted by 1.0â¯mL of HNO3, 3.0â¯mL of H2O2 and 6.0â¯mL of H2O. This condition allowed final digests with residual acidity and residual carbon content of 0.4â¯molâ¯L-1 and 6.5%, respectively. The method was validated and applied for the determination of K, Ca, Mg, S, P, Cu, Fe, Mn and Zn in 72 guarana seed samples from Bahia state. This work presents unpublished results about the mineral composition of guarana seed samples produced in Bahia state, Brazil.
Subject(s)
Food Analysis/methods , Paullinia/chemistry , Spectrum Analysis/methods , Brazil , Carbon/analysis , Hydrogen Peroxide/chemistry , Metals/analysis , Micronutrients/analysis , Microwaves , Nitric Acid/chemistry , Seeds/chemistryABSTRACT
ABSTRACT Yellow sweet potato is mostly produced by small farmers, and may be a source of energy and carotenoids in the human diet, but it is a highly perishable crop. To increase its industrial application, yellow sweet potato flour has been produced for use in bakery products. This study aimed to evaluate the technological quality and the carotenoids content in sweet breads produced with the replacement of wheat flour by 0, 3, 6, and 9% yellow sweet potato flour. Breads were characterized by technological parameters and β-carotene levels during nine days of storage. Tukey's test (p<0.05) was used for comparison between means. The increase in yellow sweet potato flour concentrations in bread led to a decrease of specific volume and firmness, and an increase in water activity, moisture, orange coloring, and carotenoids. During storage, the most significant changes were observed after the fifth day, with a decrease in intensity of the orange color. The β-carotene content was 0.1656 to 0.4715 µg/g in breads with yellow sweet potato flour. This work showed a novel use of yellow sweet potato in breads, which brings benefits to consumers' health and for the agricultural business.
Subject(s)
Bread/analysis , beta Carotene/analysis , beta Carotene/chemistry , Ipomoea batatas/chemistry , Flour/analysis , Food Handling/methods , Reference Values , Rheology , Time Factors , Food Quality , Reproducibility of Results , Color , Food Ingredients/analysis , Nutritive ValueABSTRACT
Yellow sweet potato is mostly produced by small farmers, and may be a source of energy and carotenoids in the human diet, but it is a highly perishable crop. To increase its industrial application, yellow sweet potato flour has been produced for use in bakery products. This study aimed to evaluate the technological quality and the carotenoids content in sweet breads produced with the replacement of wheat flour by 0, 3, 6, and 9% yellow sweet potato flour. Breads were characterized by technological parameters and ß-carotene levels during nine days of storage. Tukey's test (p<0.05) was used for comparison between means. The increase in yellow sweet potato flour concentrations in bread led to a decrease of specific volume and firmness, and an increase in water activity, moisture, orange coloring, and carotenoids. During storage, the most significant changes were observed after the fifth day, with a decrease in intensity of the orange color. The ß-carotene content was 0.1656 to 0.4715 µg/g in breads with yellow sweet potato flour. This work showed a novel use of yellow sweet potato in breads, which brings benefits to consumers' health and for the agricultural business.
Subject(s)
Bread/analysis , Flour/analysis , Food Handling/methods , Ipomoea batatas/chemistry , beta Carotene/analysis , beta Carotene/chemistry , Color , Food Ingredients/analysis , Food Quality , Nutritive Value , Reference Values , Reproducibility of Results , Rheology , Time FactorsABSTRACT
BACKGROUND: Capsicum peppers are known as a source of capsaicinoids, phenolic compounds and antioxidants. Brazilian Capsicum peppers are important spices used in foods worldwide. However, little information is available on the chemical composition and antioxidant activity of these peppers. RESULTS: Capsaicin, dihydrocapsaicin, total phenolic compounds and antioxidant activity were investigated in extracts of three Brazilian peppers: Capsicum frutescens, C. chinense and C. baccatum var. pendulum, in two different harvest years and at two ripening stages. The bioactive compound content was dependent on harvest year, and changes in the concentration profiles were found for capsaicin. Mature fruits of C. chinense harvested in the first year had the highest capsaicin concentration (2.04 mg g-1 fresh pepper), and mature fruits of C. frutescens harvested in the same first year had the highest dihydrocapsaicin content (0.95 mg g-1 fresh pepper). Mature fruits of C. frutescens harvested in the first year showed the major total phenolic compound content (2.46 mg g-1 fresh pepper). The total phenolic compound content was directly related to antioxidant activity. CONCLUSION: Our results suggest that phenolic compounds significantly contribute to the antioxidant activity of the investigated peppers. Also, these data add valued novel information that enhances current knowledge of Brazilian pepper fruits. © 2017 Society of Chemical Industry.
Subject(s)
Antioxidants/chemistry , Capsicum/chemistry , Plant Extracts/analysis , Brazil , Capsaicin/analogs & derivatives , Capsaicin/analysis , Capsicum/growth & development , Fruit/chemistry , Fruit/growth & development , Phenols/analysisABSTRACT
In this work a multivariate statistical tool (Derringer and Suich optimization) was proposed for the separation of seventeen capsinoids (natural and synthetic) using the UHPLC-DAD chromatography. Capsinoids were analyzed at 280 nm. The variables optimized were the mobile phase (water (0.1% acetic acid as solvent A) and acetonitrile (0.1% as solvent B)), gradient time and flow rate. Two columns with different length (50 and 100 mm) were used for the chromatographic separation. The two columns used properly separated the seventeen capsinoids, however the 100 mm column length showed a better chromatographic separation with a shorter run time and smaller peak widths. These results provided better values of limit of detection and quantification for the 100 mm column length. The better conditions of separation with the 100 mm column length were established with: initial mobile phase with 41.8% of solvent B; 3.96 min of linear gradient time to reach 100% of solvent B; flow rate of 0.679 mL min(-1). A validation of the method has been done with excellent values of repeatability (RSD<1.92) and intermediate precision (RSD<3.92). The developed method has been applied to real samples. Capsiate has been identified and quantified in some varieties of peppers.
