The utilization of acid-tolerant bacteria on ethanol production from kitchen garbage

In order to achieve ethanol production from kitchen garbage under non-sterilized fermentation, the acid-tolerant Zymomonas mobilis named GZNS1 was selected and applied in the fermentation system. Ethanol production from kitchen garbage under non-sterilized fermentation with GZNS1 was proved to be feasible. The utilization of control strain and acid-tolerant strain under different conditions demonstrated that the sequence of ethanol yield was followed: sterilized garbage with control strain inoculated under pH of 6 (52 g/L) ≈ sterilized garbage with GZNS1 inoculated under pH of 4 (48 g/L) > non-sterilized garbage with GZNS1 inoculated under pH of 4 (46 g/L). Furthermore, the distillery waste during fermentation was adopted to recycle fermentation and acquired 50 g/L ethanol, higher than those adjusted with tap water. The utilization of acid-tolerant bacteria combing with the utilization of distillery waste associated with the process can increase ethanol production, save energy and reduce the cost of ethanol production.