In this study, the cultivation of lactic acid bacteria was done using vinasse (with a chemical oxygen demand of 378 ± 5 g O2/L) to harness its organic content. The potential for biomass and lactic acid production was evaluated by using strains Lactococcus lactis subsp. Cremoris and Lactococcus lactis subsp. Lactis. Before medium preparation, vinasse was pretreated with air and ozone to reduce inhibitory load. The effects of pretreated vinasse addition on lactic acid bacteria growth were in the range of 0–33% v/v. The optimal vinasse concentration for obtaining high biomass and lactic acid concentrations was 17% v/v, leading to maximum concentrations of biomass and lactic acid of 2.2 ± 0.14 and 16.0 ± 0.9 g/L, respectively. Fed-batch operation was also studied as a strategy for extending the production phase of lactic acid bacteria using vinasse (17% v/v) as feeding. These results highlight the underexplored potential of vinasse as an economical source of raw material for obtaining value-added products through biotechnological processes.
Key words: vinasse, bioethanol, lactic acid, sugarcane, lactic acid bacteria
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