Seleção de leveduras nativas do brejo paraibano para produção de cachaça

Abstract

Cachaça has economic, social and cultural importance in the micro-region of the Brejo Paraibano. For cachaça production, fermentation corresponds to the central mechanism of the process, being a biological phenomenon carried out by yeasts. The selection of yeast strains is essential to maximize the alcohol yield, to maintain the sensory quality of the beverage produced and when it comes to native microorganisms, it promotes a regional identity to the product. Therefore, the objective was to select native yeasts from the Brejo Paraibano for cachaça production. The experiment was carried out at the Agroindustrial Complex, on Campus II of the State University of Paraíba, Laboratory of Food Microbiology, Lagoa Seca, Paraíba, Brazil. Initially, sugarcane was collected in the municipalities of Areia-PB, Lagoa Seca-PB, Alagoa Nova-PB and Alagoa Grande-PB. Afterwards, the plants were cut and taken to the mill at the aforementioned Agroindustrial Complex to be milled. The broth obtained was kept in glass flasks at room temperature for 24 hours, in order to obtain the maximum diversity of native yeasts. An aliquot of the solution was collected and inoculated into a Petri dish. Colonies with typical yeast morphology were collected and transferred to test tubes with culture medium for use in selection tests. 126 pure colonies were obtained, divided into four groups: A (32), B (42), C (38) and D (14). Yeast strains were selected based on four exclusion tests: 1) Production of hydrogen sulfide (H2S); 2) Fermentation of glucose; 3) Ethanol tolerance; and 4) Growth at 37ºC. Strains A11 and D8 were promising, as they did not produce hydrogen sulfide, were tolerant to glucose fermentation and ethanol concentration, finally, reached growth at a temperature of 37ºC, being recommended in future research for cachaça production in the Brejo Paraibano.