Fermentação semissólida de okara com Saccharomyces cerevisiae r. f. bayanus visando a biotransformação de isoflavonas e melhoria da qualidade nutricional

Abstract

Okara is a biomass generated by the soybean and tofu water soluble extract process. Such biomass has a very important nutritional quality because of the protein content, fibres and bioactive compounds as the isoflavons. It is produced in great amounts by the soybean processing industry as a by-product, although it is a product of low commercial value, it possess on its composition molecules with nutritional and functional potential. The isoflavons are present in the soybean mainly in the combined forms (B-glycosidics, acetyl and molonic) and, in a minor proportion, in the free forms (aglycons). Several studies prove the efficiency of aglycons isoflavons preventing cronicle diseases. Some technologies have been employed for the bioconversion of β-glycosidic isoflavon in aglycons based in the action of enzymes β-glycoside hydrolase synthesized by microorganisms. In this context, the current work has aimed the bioconversion by Saccharomyces cerevisiae r. f. bayanus, trying to improve the okara nutritional quality and biological properties in order to use it as an ingredient in food. The semisolid fermentation has been lead under 28° C per 72 hours. The process was conduction at increase protein and reduction of crude fiber content improving the product digestibility. The fermentation provided a biotransformation of isoflavonscombining aglycons, what has taken to the raise of amount of phenolic compounds, biomasa antioxidant capacity and consequently improving of nutritional quality. The biotransformation of okara isoflavons by fermentation process has should to be a promising strategy for adding value and better use of biomass.