利用台灣農產原料釀製日式燒酎之研究

摘要本研究利用台灣農產原料米，紅甘薯，黃甘薯，黑糖，以及進口的濃縮麥芽精為原料，試驗製造日本燒酎。利用黃麴菌（BCRC 30428）製造麴米，以提供分解澱粉質原料所需要的糖化酵素，酒精發酵則採用一株日本燒酎用的酵母菌（BCRC 22292）。先以麴米，酵母菌製造酒母之後（一次醪），再加入蒸煮過的原料與麴米進行發酵（二次醪）。發酵完成的燒酎則以常壓蒸餾，分別擷取酒精度19～40度及40～55度兩段酒液裝瓶，在常溫密封貯存三個月後，取出以氣相層析儀做香味成分分析。各種類燒酎之主體香味成分有羰基化合物、酯類、高級醇類、芳香族化合物構成，而其中以高級醇類所佔香味成分的總百分比最大（13~83%）。主要高級醇類為n-propanol、i-butanol、2-methyl-butanol(2-甲基丁醇)、3-methyl- butanol (異戊醇)，其中以異戊醇含量最高。至於酯類香氣占總體香味成分的 1~5% 不等，乙酸乙酯以及己酸乙酯皆因濃度太稀，用我們現有的儀器測不出來，反而是高沸點的酯類如，乳酸乙酯則有出現。研究結果顯示高酒精度的燒酎收集的香氣成分較佳，若要勾兌成低酒精度的燒酎商品，也應該利用高酒精度的燒酎為原料較好。

關鍵字

米，紅甘薯，黃甘薯，黑糖，麴

並列摘要

Abstract Shochu is a tranditional Japanese spirit. The present study employed local agricultural products such as rice, sweet potato (red and yellow), brown sugar, and malt extract to make shochu in small scale. We used Aspergillus oryzae (BCRC 30428) as strain for koji rice and Saccharomyces cerevisiae (BCRC 22292) for Shubo (yeast starter) in our study. The Shubo mixed with steamed raw materials (rice and sweet potato), or brown sugar, malt extract for further fermentation for 2 weeks. The broth was distilled at 1 atmosphere. Distillate was collected for alcohol content above 40 % (v/v) as high alcohol shochu, and 19~40 % (v/v) as low alcohol shocho. The shochu was stored in room temperature for three month. The flavor compounds of shochu were analyzed by gas chromatography. The flavor compounds of shochu from gas chromatography can be clssified as carboxylic compounds, esters, higher alcohols, and aromatics. The higher alcohol shochu composed the major flavors (13 ~ 83 %). The major flavors are n-propanol, i-butanol, 2-methyl butanol, 3-methyl butanol. Among them, 3-methyl butanol is the most flavor compound. The esters are relatively low in concentration. Ethyl lactate cound be found in all of the shochu samples. The flavor compounds for high alcohol shochu are better than those for lower alcohol shochu. It is recommended to dilute high alcohol shochu to make low alcohol shochu product.