Estudo da secagem do bagaço de uva visando à sua utilização como ingrediente na formulação de barras de cereais

Abstract

The grape pomace present in its composition a high content of polyphenols with antioxidant activity, characterizing it as a product that could be used more profitably by industry, for example, in the formulation of food for humans. Drying is a method of reducing the moisture content of the foods that can be a tool for use of grape pomace. The purpose of this study the effect of time and drying temperature on the content of phenolic compounds and antioxidant capacity of grape pomace for later obtaining the flour and its use thereof in the formulation of bars was to evaluate cereal bars. The experiments were conducted at different temperatures (40°C, 50°C and 60°C) and the experimental data were fitted to six mathematical models, being compared with respect to the best values of determination coefficient (R2) and the residual sum of squares (SQR). The behavior of bioactive compounds along the drying process at different temperatures was also evaluated. The Page model was selected as the most adequate to represent the convective drying of grape pomace. Treatments showed significant difference in the retention of phenolic compounds and antioxidant capacity. The pomace dried at 60°C showed the highest levels of phenolic compounds and antioxidant capacity, suggesting that this temperature was able to inactivate enzymes that catalyze the degradation of phenolic compounds. Drying new tests were performed and from these a flour was obtained from grape pomace, after being characterized been used as an ingredient in different concentrations for the formulation of cereal bars. These products against the content of bioactive compounds and antioxidant capacity were evaluated. The cereal bars with the highest levels of flour had the highest concentrations of bioactive compounds and antioxidant capacity, being a great alternative to enrichment of food products.