Influência do tratamento enzimático na etapa de fermentação da produção de cachaças

Abstract

Cachaça is the fermented and distilled beverage obtained from sugarcane juice, with peculiar sensory characteristics. It is estimated that in Brazil, in 2015, 8 million liters were produced, and cachaça was exported to more than 60 countries, showing its economic importance. Despite this, its production process has a low yield and still generates a large volume of waste (bagasse and stillage). Thus, several strategies must be evaluated aiming not only to optimize fermentation but also to obtain cachaças with a different chemical profile, contributing to the increase of sensory attributes and adding greater market value. Among the strategies, the following stand out: pre-treatment of sugarcane juice; the use of non-conventional microorganisms, and the incorporation of bioactive compounds. Thus, this work aimed to produce ligninolytic enzymes by Streptomyces thermocerradoensis I3 in wheat bran and rhizome flours from two vegetables extracted from the Cerrado soil: Cochlospermum regium and Jatropha elliptica, to obtain enzymatic extract for later application in the pre-treatment of sugarcane juice to obtain cachaça. It was observed that the wheat bran proved to be the best of the tested medium and that the extracts produced were able to promote the hydrolysis of the flours, which promoted an increase in the concentration of reducing sugars and total phenolic compounds, suggesting the use of this extract for saccharification in flours, promoting greater access to these compounds. In the second stage of the study, the objective was to use the enzyme obtained from Streptomyces sp. I7 in the pre-treatment of the sugarcane juice, for subsequent fermentation of this juice using three different microorganisms: Saccharomyces cerevisiae; yeast to produce Belgian Ale beer (M27), and finally a microorganism isolated from sugarcane juice from spontaneous fermentation. It was found that regardless of the microorganism used in the fermentation step, the pre-treatment with the enzymatic extract promoted an increase in ethanol production. Also, the enzymatic pretreatment generated cachaças with distinct chemical profiles proven by nuclear magnetic resonance analysis. Finally, the use of enzymatic extract associated with low-frequency ultrasound for the incorporation of phenolic compounds extracted from Zingiber officinale Roscoe in cachaça acquired in the local market was evaluated. It was found that the method employed favored the extraction of reducing sugars and phenolic compounds, with emphasis on gallic and caffeic acids. The consumption of alcoholic beverages with a higher content of phenolic compounds, when compared to the consumption of beverages without these components, could bring benefits to the health of consumers.