Large-scale fermentation of Lactiplantibacillus pentosus 292 for the production of lactic acid and the storage strategy based on molasses as a preservative

Abstract

A cheap medium containing 30 g/L glucose, 15 g/L yeast powder, 8 g/L K2HPO4, and 10 g/L tween-80 was developed for Lactiplantibacillus pentosus 292, and the lactic acid (LA) produced in this medium was up to 16.24 g/L increased by 83.48% compared with that in MRS medium after 24 h fermentation under optimal condition (temperature 35 ℃, pH 6, shaking speed 100 rpm, and inoculation amount 3%). Subsequently, the large-scale fermentation kinetics models of bacterial growth, substrate consumption, and product generation in a 200-L fermenter were built using better-fitting models of Logistic, Luedeking, and Luedeking-Piret, respectively. Then, the preservation strategy of fermentation broth with 1–3% molasses as preservative and temperature acceleration experiment were studied. This work besides constructing the large-scale fermentation kinetics models of L. pentosus 292, also developed a storage strategy based on the molasses as a preservative, thereby facilitating the application of 292-strain for large-scale production of lactic acid bacteria (LAB) preparation and its products.