Effect of Different Fermentation Parameters on Lactic Acid Production from Kitchen Waste by Lactobacillus TY50

X. Wang, Q. Wang, X. Wang and H. Ma

Abstract
Effects of different fermentation parameters including temperature, pH and oxygen on lactic acid (LA) production from kitchen waste were investigated in order to establish optimum regulating measures and increase LA yield. An open fermentation mode was employed for achieving simultaneous saccharification and fermentation of kitchen waste with Lactobacillus TY50 as inoculum. The results showed that 45 °C was optimum temperature for synergistic relationship between inoculated strain and indigenous strains, resulting in higher LA concentration. Continuous pH adjustment to 6.0 resulted in the similar LA concentration with intermittent pH adjustment to 7.0. However, LA productivity for continuous pH adjustment was much higher than intermittent pH adjustment. Compared to anaerobic fermentation, aerobic condition resulted in a decrease in LA concentration and an increase in acetic acid concentration. LA concentration could reach to 36.29 g L–1 with 1.01 g L–1 h–1 of productivity and 0.44 of yield (LA/dry mass) from kitchen waste fermented anaerobically by Lactobacillus TY50 at 45 °C and pH 5.5–6.0.

This work is licensed under a Creative Commons Attribution 4.0 International License

Keywords
kitchen waste, lactic acid, Lactobacillus, fermentation