XXXV Reunião Anual da SBBqResumoID:8243


Isolation, characterization and tolerance induction of Saccharomyces cerevisiae strains from five Espirito Santo State distilleries.


Bravim, F.; Petri, M.;Garcia, R.;Fernandes, P. M. B.

Núcleo de Biotecnologia, Universidade Federal do Espírito Santo, Vitória, Espírito Santo, Brazil. *biotecnologia.ufes@gmail.com


Cachaça, the most traditional beverage in Brazil, with alcoholic content of 38 to 54 ºGL, is obtained by sugarcane juice fermented must distillation. Saccharomyces cerevisiae is the main organism responsible for sugar decomposition to ethanol and carbon dioxide in the fermentation vats. Moreover, this yeast is physiologically adapted to the multiple stress conditions observed during the fermentation process. Alcoholic strains of S. cerevisiae are available in the market; however, those strains are not selected for the desired fermentation conditions. Our goal was not only to select yeast strains but also to induce resistance to the conditions presented at the cachaça fermentation vats for Espirito Santo State’s producers. Samples were collected from five different distilleries and 15 S. cerevisiae strains were isolated. Fermentation was achieved by the addition of 20% cells of the selected strains to sugarcane juice. Samples were collected and analyzed for sugar consumption, ethanol production and titratable acidity at different time points (0, 4, 6, 8, 12 e 24 h). As a control, a strain from the market was used. Better results were observed for strains selected from the State mountain region distilleries, which showed a high fermentative efficiency and low acidity, promoting a better final product. Moreover, the strains selected from each distillery still showed a better fermentative activity then the market strain. The yeast strain that revealed the best results was submitted to a mild hydrostatic pressure treatment at room temperature to induce tolerance, therefore increasing its fermentation capacity. The results obtained in this work clearly show that the best approach for high quality cachaça production is a local selection of yeast strain and from this to induce stress resistance.

 

Supported by: CAPES, CNPq, FAPES and FINEP.