Optimization of lactic acid production from food waste by the saccharification of Bacillus subtili

摘要

In order to reduce the costs of production and increase the lactic acid yields,this research adopts Bacillus subtilis to substitute enzymes.The method used in the study is two-phase fermentation - inoculate Bacillus subtilis to food waste to produce sugar,and then inoculate Lactobacillus to food waste to yield lactic acid.87.22 g l-1 of total sugar can be obtained from non-autoclaved food waste in 30 h of saccharification at 40 centigrade.After two-phase fermentation,the optimal lactic acid concentration was 50.77g/L.The results indicate that two-phase fermentation is better than synchronous saccharification fermentation.