Isolamento e seleção de leveduras fermentadoras da cana-de-açúcar para produção de cachaça na região do brejo paraibano

Abstract

The Paraiba swamp has stood out on the national scene in the production of cachaça, which has gained strength over time not only due to the volume produced but also by the quality of the product. One of the main stages in the production of cachaça is fermentation, a biological process carried out by yeasts in the vats. The quality of the final product is directly linked to the characteristics of the strain in action. Knowing that yeasts from different origins carry marks of their regionality in the metabolism, the problem arises in the scenario in which the selected yeasts available commercially come from the south-central part of the country. The objective of this work was to select native yeasts from the Paraiba swamp that have the best efficiency profile in the fermentation process, allowing to enhance the quality of the local product, consolidating the regional identity. All stages of the research were carried out at the UEPB Agroindustrial Complex, in the municipality of Lagoa Seca, Paraiba. The cane was ground right after collection and the juice was reserved for 24 hours. The broth was then diluted and inoculated in Petri dishes, which were incubated for 48 hours. Isolated colonies were collected and preserved, and then subjected to selection tests. The isolates was analyzed by the glucose fermentation, ethanol tolerance, hydrogen sulfide production and high temperature resistance tests, and those with a positive character for glucose fermentation, ethanol and high temperature tolerance and negative for production of hydrogen sulfide was selected. 158 colonies were isolated, which, after all exclusion tests were performed, only one strain, isolate B5, showed favorable behavior in all tests. The results confirmed the great metabolic diversity in native yeasts, reinforcing the importance of exploring the regional microbiota.