Cassiano Oliveira da Silva

Sensory evaluation and nutritional value of cakes prepared with whole flaxseed flour

The objective of this study was to evaluate the nutritional value, the oxidative stabilitiy, and consumer acceptance of cakes containing four different concentrations of flaxseed flour (5, 15, 30 and 45%) as partial replacement for wheat flour. The oxidative stability of polyunsaturated fatty acids was evaluated through the lipid peroxidation test (TBARS) in the flour and cakes. Linolenic acid was determined by gas chromatography as well as contents of protein, lipid, ash, and dietary fiber. Consumer acceptance was assessed using a structured hedonic scale of nine points. The oxidative stability of lipid flaxseeds was not affected by the heat treatment during flour processing and cake baking. Cakes made with 5, 15, and 30% of flaxseed flour, the most accepted by consumers, had dietary fiber levels ranging from 3.5 to 6.2 g and linolenic acid ranging from 445 to 2,500 mg.100 g –1 of the product. The cakes received claims of good and excellent source of dietary fiber and linolenic acid, respectively, both are bioactive compounds. The use of up to 30% of flaxseed flour in the preparation of cakes is a useful strategy to optimize the consumption of food rich in functional ingredients.

Influência do processamento na qualidade proteica de novos cultivares de soja destinados à alimentação humana

OBJECTIVE: The aim of this study was to evaluate the effect of processing on the protein quality of new soybean cultivars intended for human food. METHODS: The diets were prepared from the cultivars Embrapa 48, BRS 213, BRS 155 and UFVTN 105. They were heat-treated in a vacuum oven at 130oC and 150°C, with subsequent removal or not of the hull for the production of soybean meals. A biological assay was done to determine the protein efficiency ratio, net protein ratio and true protein digestibility. RESULTS: Soybean meals had lower protein efficiency ratio, net protein ratio and digestibility than casein. Whole soybean meals treated at 150oC had a better protein quality index than refined soybean meals heat-treated at 130oC. The protein efficiency ratio and net protein ratio of Embrapa 48 and BRS 155 cultivars were higher (p<0.05) than the other ones. The UFVTN 105 cultivar had the highest digestibility (p<0.05) when treated at 130oC. Among the cultivars heat-treated at 150oC, the BRS 213 and BRS 155 cultivars had the lowest digestibility (p<0.05). Protein digestibility of the cultivar with low trypsin inhibitor content (BRS 155) was not better than that of the conventional Embrapa-48 cultivar. CONCLUSION: Heating and removal or not of the hull affected the protein quality of the new soybean cultivars intended for human food. Whole soybean meals heat-treated at 150oC for 30 minutes presented the best results. Heating improved the protein quality of the conventional soybean meals. Their protein quality was similar to that of the cultivars without trypsin inhibitor and better than that of the cultivars without lipoxygenases.

Evaluation of the chemical composition, protein quality and digestibility of lupin (Lupinus albus and Lupinus angustifolius)

The purpose of this study was to determine the protein quality of lupin (Lupinus albus and Lupinus angustifolius) and to determine their chemical composition, including dietary fiber. The food transformation index, protein efficiency ratio and net protein ratio were significantly higher for the casein group than for the lupin groups. The in vivo digestibility value of casein was 95.81 ± 1.60, and the DV of L. albus and L. angustifolius were 90.89 ± 2.85 and 89.30 ± 2.01, respectively. Amino acid composition scores lower than one were found for almost all essential amino acids in lupin groups. The protein digestibility corrected amino acid scores ranged from 40.00% to 89.07% for L. albus and from 30.36% to 83.05% for L. angustifolius. It was concluded that the two varieties of lupins studied are good protein sources, with no statistical difference between them, and also that this protein has an excellent digestibility, besides being a good source of dietary fiber, especially Lupinus angustifolius. Therefore, the two varieties of lupine were considered as having good quality protein and as being a good alternative for human consumption.