Efeitos do tempo de encharcamento sobre parâmetros de avaliação tecnológica e nutricional de arroz parboilizado

Abstract

Rice, second most produced cereal in the world, it s important to Brazil, where it is consumed by over 90% of Brazilians. In parboiling process occurs migration of nutrients from germ and peripheral layers inside the caryopsis, higher incomes industrial, shelf life and nutritional value of grain. In the lipid fraction is found - oryzanol, a nutraceutical compound with high antioxidant activity and pharmaceutical applications, cosmetic and food industry. Significant increase in parboiled rice consumption contributes to the search for knowledge about parboiling process and benefits conferred by him. The aim of this study was to evaluate effects from industrial processing and hydratation time in parboiling on technological parameters, evaluation of nutritional quality, sensory attributes, lipid profile and -oryzanol. Were used long thin class grains, produced in the irrigation system. The oil samples were derivatized using BF3-MeOH and analyzed by gas chromatography. The -oryzanol fraction was analyzed by mass spectrometry with electronebulization (ESI). The data were analyzed by variance analysis and means compared by Tukey test at 5% significance level. The results show that parboiling causes changes in the attributes sensory, increase whole grains yields, concentrations of protein, fiber, oil and ashes in the polished grains, and firmness, chewiness and gumminess of cooked rice grains, with reduction of adhesiveness and profile whiteness. The increase of hydratation time does not change -oryzanol fraction nor lipid profile of rice oil, but promotes changes in attributes sensory, as increase in the adhesiveness and reduction in the chewiness, gumminess and firmness of cooked grains and at whiteness profile.