Fermented CM (FCM) was prepared by placing CM in a set of 125 ml capacity anaerobic serum bottles. The headspaces of the bottles were purged with N2 gas, and the vials were sealed with rubber stoppers and crimped aluminum caps. These bottles were incubated anaerobically at 55 C. Biogas produced was monitored everyday. When gas production stopped, vials were opened; FCM produced was collected and kept under 20 C until use