Traditionally, the yeast is propagated directly in the fermentation vats in sugarcane spirit factories. However, they have no devices to optimize the propagation, in which the aeration efficiency is a key factor in the prevalence of the respiratory metabolism to maximize yeast reproduction and minimize the formation of ethanol. This study evaluated the growth of the yeast Saccharomyces cerevisiae in equipment with both simple batch and semi-continuous aeration systems using complex or agro industrial media. The use of aerated equipment allowed for greater substrate conversion to cells and reduced the levels of ethanol and acids produced. The propagation carried out by the semi-continuous process was more efficient than that with the simple batch system. The use of an agro industrial medium supplemented with a protein source, as usually done in the propagation of yeast for the production of sugarcane spirit, provided the greatest increases in biomass and the best parameters for propagation as compared to a complex medium. These results will contribute to the development of an operational protocol for propagation of the yeast to be used in the production of sugarcane spirit.
Cachaça; Yeast; Biomass increase; Fermentation
