Extração de amido, processamento e caracterização físico-química, nutricional e estudo de estabilidade em farinhas (integrais, decorticadas e germinadas) cruas e pré-cozidas por extrusão de milheto, destinadas ao consumo humano

Abstract

The Food and Agriculture Organization of the United Nations declared 2023 as the International Year of Millets, as an opportunity to promote this cereal, contributing to sustainable development and nutritional improvement. Pearl millet [Pennisetum glaucum (L.) R. Br.], originally from the African continent, is a gluten-free cereal, widely cultivated and consumed in Africa and Asia, for animal and human consumption, capable of growing in adverse drought conditions. In Brazil, its potential is underused as a forage crop and animal feed, although its grains contain many components that promote human health. It stands out in millet grains, high fiber and protein contents. However, one of the factors that lead to low consumption is the high lipid content, contributing to the development of oxidative reactions. Extrusion processing can be an alternative for the stability of millet flours. Thus, this study aimed to evaluate the impact of processing on extruded millet (hybrid ADRg 9070) and its extruded flours, in relation to physicochemical and nutritional properties, in vitro digestibility of carbohydrates, as well as to extract and evaluate the starch of millet and to evaluate the physical-chemical stability of extruded flours. The results showed that, despite having less radial expansion, the millet extrudates and their extruded flours had up to 20% more protein, 32% more dietary fiber and 20% less carbohydrate digestibility when compared to the same corn products, evidencing the superiority millet nutrition; millet starch showed resistance to paste formation associated with low viscosity in hot processing (below 80 °C); which may be related to the lower expansion found in millet extrudates, finally, in the stability study of extruded flours, extrusion processing was able to increase the stability of these flours in up to 3 months, compared to raw flours. Therefore, extrusion processing on millet flours contributed to an increase in physicochemical stability, as well as greater nutritional value when compared to the same corn products.