1990 Volume 85 Issue 4 Pages 269-276
Production of Spirits from Uncooked Corn Grits by Solid-State Ethanol Fermentation System.
Production of spirits from uncooked corn grits by a pilot-scale solid-state ethanol fermentation system (SSEF) was investigated. When the ethanol fermentation is done by SSEF, the recovery of ethanol by circulating CO2 is more effective at high temperature than at lower temperature. Because the corn grits are not heated by the steam, there are high possibilities of contamination by bacteria and molds (fungi) in fermentation. To protect the mash against the contamination, fermentation tests were done by the use of some lactate buffer or lactic acid solutions. Among these. liquids, pH 3.5, 0.2 M lactate buffer was the optimum for fermentation and protection against the contamination. Lactate buffer solution (pH 3.5, 0.2 M) containing saccharifying enzyme and moderately thermophilic yeast (Saccharomyces cerevisiae 1031 R) was added to the uncooked corn grits in the fermentor and the fermentor was kept at 40°C. The fermentation was continued for 9 days, and ethanol produced was 399 g/kg-IDM (initial dry mass). The content of acetaldehyde in the product was about 8 times as high as that in conventional type spirit “shochu”.
