Abstract
To clarify the causes of fermentation inhibition during ball-vibration simultaneous saccharification and fermentation (BVSSF) used for conversion of spent maitake (Grifola frondosa) culture medium to ethanol, we investigated the effects of various factors on BVSSF in detail. The BVSSF was carried out by shaking a plastic bottle containing stored maitake culture medium, cellulase, yeast and various sizes of zirconia balls. The effects of zirconia ball size (diameter of 1, 3, 5 or 10 mm) and shaking speed (100 or 200 rpm) on ethanol conversion during BVSSF were analyzed. The results indicated that physical stress may affect ethanol production ability of yeast.
