Extrusão termoplástica de farinha de arroz com café torrado e moído e sua utilização em produtos de panificação

Abstract

This work was intended to manufacture pre-cooked flours of mixtures of rice with coffee powder utilizing thermoplastic extrusion and verify its viability as a functional food with sensorial quality. The independent variables utilized during the extrusion process were moisture, temperature and percent of coffee powder in the mixture with rice. The physical characterization of the produces was performed by means of expansion index, of apparent density, of the absorption index, of water solubility and of viscosity of initial, maximal and final paste. Sensorial tests of preference were accomplished in four samples: two of biscuits and two of cakes manufactured with the extruded flours of coffee powder/rice (15:85, 20:80 w:w). These flours were utilized at the ratio of 20 and 30% in the wheat doughs (80 and 70%), respectively. The results obtained show significant differences for all the chemical constituents analyzed in the coffee powder and raw rice flour, respectively: moisture, 4.89 and 12.44; lipids, 11.60 and 0.69; crude protein, 15.75 and 7.32; total carbohydrates, 6.92 and 79.08; ashes, 4.48 and 0.47, total fibers, 14.22 and 1.57g/100 and caloric value, 419.08 Kcal and 351.81. In the products manufactured, that is, biscuits and cakes the centesimal composition the presented the following results : lipids, 7.62 and 8.40; crude protein, 7.62 and 7.88; total carbohydrates 75.65 and 76.05; ashes 1.39 and 1.49; total fibers , 2.80 and 3.0 g/100g and caloric value, 400.06 and 410.88 Kcal. The biscuits and cakes manufactured with the treatments which presented the best results of IAA and ISA processed with 15 and 20% of coffee powder in the mixture demonstrated through sensorial analysis, their viability for manufacture of cakes with both treatments for not presenting any differences for statistical differences from one another for all the evaluated parameters preference for aroma and texture relative to the one manufactured with 20%. The information obtained in this research point that its is viable from the technological and sensorial standpoint, the making of products obtained through the thermoplastic extrusion of rice flour with coffee powder.