Lactic acid production and cell viability of Lactobacillus plantarum inoculated into sugarcane juice (Saccharum spp.) supplemented

Abstract

Silage inoculation with lactic bacteria is an efficient technological advance used for ensuring high initial concentration of those bacteria that are multiplied in good conditions, allowing intensive lactic acid production and a prompt and efficient fermentation. Whereas many subproducts and raw materials have been used as a viable culture medium for microorganism growth of biotechnological interest, this study aimed to verify the best composition of a culture medium, and had sugarcane juice in different soluble solids concentrations (^oBrix), yeast extract and ammonium sulfate as independent variables which were evaluated in three equidistant levels of variation through experimental design of 2³ central combination by response surface methodology (RSM); the dependent variables were lactic acid production and Lactobacillus plantarum viable cells, both denoted as response function. The best condition for lactic acid production (1.53%) and L. plantarum viable cells (8.63 log CFU mL^-1) was the culture medium containing sugarcane juice at 5 ^oBrix, supplemented with 1.1% yeast extract, and 1.1% ammonium sulfate.