麸皮红曲发酵工艺研究

Study on Fermentation Technology of Bran Red Koji

麸皮是培养麸曲的良好原料,红星公司目前以大米或小米培养红曲,成本较高,以麸皮培养红曲替代大米红曲或小米红曲以降低生产成本具有一定的现实意义。优化麸皮红曲发酵工艺条件,分析红曲的风味物质,进行红曲制曲成本分析。以糖化力为麸皮红曲的评价指标,通过单因素试验和正交试验,确定了麸皮红曲发酵的最佳条件:装料量30 g/500 mL三角瓶、接种量20%、初始加水量120%、温度30℃。对红曲进行气相色谱分析,两种红曲中含有9种风味物质,醛类2种,醇类2种,酯类5种,它们的含量差异与制曲原料有关,麸皮红曲的醛类物质、酯类物质含量高于大米红曲,分别高53.34%、3.82%,但醇类物质含量低于大米红曲,约低9.08%。经过制曲成本分析,麸皮红曲直接原料成本远低于大米红曲直接原料成本,具有经济可行性。

Bran is a good raw material for cultivating bran koji.Currently,Red Star Company uses rice or millet to cultivate red koji with higher cost.Therefore,it is of practical significance to replace rice red koji or millet red koji by bran cultivated red koji.It is also valuable to optimize the fermentation conditions of bran red koji,analyze the flavor substances of red koji and the cost of red koji making.The optimal fermentation conditions of bran red koji are determined by single factor experiment and orthogonal experiment,using the saccharifying power as the evaluation index of red koji,the content of bran is 30 g/500 mL triangular flask,the inoculation amount is 20%,the initial water additive amount is 120%,and the temperature is 30℃.Through gas chromatography analysis,the two kinds of red koji contain 9 kinds of flavor substances,including 2 kinds of aldehydes,2 kinds of alcohols and 5 kinds of esters.Their content differences may be related to the raw materials of koji making.The content of aldehydes and esters in bran red koji is 53.34%and 3.82%higher than that in rice red koji respectively,but the content of alcohols is 9.08%,lower than that in rice red koji.According to the cost analysis of koji making,the direct raw material cost of bran red koji is much lower than that of rice red koji,which is economically feasible.