本研究利用液態發酵的方法,進行高粱酒的釀造實驗,先將高粱磨粉,加水配成25%的高梁醪,此高粱醪加入澱粉液化酵素、蛋白質分解酵素、纖維素水解酵素,在80℃進行液化作業2小時,之後再加溫到 100℃進行1小時。此高粱醪降溫後加入葡萄糖水解酵素以及五種活性酵母,分別進行同步糖化與發酵作用,發酵後的酒醪,進行蒸餾程序,收取酒精度20% (v/v) 以上的部分,調和成50% (v/v)的高梁酒,此液態發酵完成的高粱酒利用GC-MS分析其香氣成分,並與傳統的固態發酵之高粱酒比較,發現本研究之高粱酒的酯類香氣與有機酸都很低,而高級醇類則比較高。推論傳統固態發酵的高梁酒使用的麴餅含有豐富的微生物菌相包含細菌類的醋酸菌與乳酸菌,這些細菌在酒醪中發酵得到合成酯類香氣的有機酸如醋酸與乳酸。若要利用液態發酵的方法得到傳統固態發酵的酯類香氣,則需利用串香的技術來達成。
The present study employed liquid culture technology in kaoliang liquor production. The sorghum was milled to power, and mixed with water to a 25% (w/v) mash. The sorghum mash was hydrolyzed by 脉-amylase, protease and cellulase at 80牵C for 2 h, and then cooked at 100牵C for 1 h. The hydrolyzed sorghum mash was cooled to room temperature, the glucoamylase and yeast was added to perform simultaneous saccharification and fermentation process. The fermented sorghum mash was distilled, and the alcohol content more than 20% (v/v) was collected. The resulted kaoliang liquor was blended with water to 50% (v/v) alcohol content. The volatile flavors were analyzed by GC-MS, and compared with those from the traditional solid culture. The results indicated that the contents of esters and acids by liquid culture were less than those by solid culture. However, the contents of higher alcohols were more by liquid culture. A special blending technique must be applied to enhance the ester flavors.