Redução do pH da água de encharcamento na parboilização de arroz e seus efeitos nas características tecnológicas, parâmetros nutricionais e de digestibilidade in vitro.

Abstract

Rice is considered a staple food for more than half of the world's population. It is one of the main sources of energy for humans because of its high content of carbohydrates, proteins, minerals and B-complex vitamins. to evaluate the effects of the use of citric acid and sodium bisulfite in the process of parboiling to improve parameters of technological and nutritional evaluation, parboiled rice grains and technological parameters, and the digestibility of Indian and Japanese rice grains. It was used rice grains (Oryza sativa L.), long-fine class (needle) with high amylose content (26%) and the short class with 16% amylose content, where the hydration curve of rice with the addition of citric acid and sodium bisulfite. The hydration solution was adjusted to pH values: 6, 5, 4, 3, 2 and 1 with citric acid and with the use of sodium bisulfite in a ratio of 1: 2 (w: v of rice: volume of the solution)). The reduction of the rice hydration time of 300 min was observed. of the control for 210 min. in the treatment AP6 and AP12 (pH 1) and had improvements in the color of parboiled and polished grains as can be observed in the L * and b * values of 59.27 and 23.10 when compared to AP1 treatment, reduction of cooking time of rice with a reduction of more than 6 min. in the more drastic treatment (with pH 1), softer grains were obtained in AP12 treatment. It was observed that treatment with sodium bisulfite obtained the whiter grains and that AP11 and AP12 treatments reduced the cooking time and had softer grains, but decreased the yield of integers by weakening the proteins that are denatured by reducing the pH. The rice indicated with 26% amylose had lower digestibility when compared to the Japanese rice with 16% amylose.