米曲霉沪酿3.042发酵酱油制曲的条件优化

Optimization of Conditions of Koji-making for Fermented Soy Sauce by Aspergillus oryzae Huniang 3.042

以米曲霉沪酿3.042为发酵酱油菌种,豆粕和麸皮为原料制曲,研究原料配比、润水量、原料变性时间、制曲温度对制曲过程中蛋白酶(酸性蛋白酶、碱性蛋白酶、中性蛋白酶)、淀粉酶活的影响,得到制曲过程中优化的条件:豆粕∶麸皮为2∶3,最适润水量为120%,蒸料时间为20min,制曲温度为30℃时,能够明显增加孢子成熟速度,白色菌丝生长厚实,曲味浓郁,有独特香味,此时产生的蛋白酶和淀粉酶的酶活性较高,最适于曲料发酵。

This research aims to analyze the effects of raw material proportion, moistening level, raw material degeneration time and koji-making temperature on activity of protease （acid protease, alkaline protease and neutral protease） and amylase during koji-making progress, which uses Aspergillus oryzae Huniang 3.042 as strain for fermented soy sauce and soybean meal and bran as raw materials. The results indicate that the optimal conditions for koji fermentation are that the proportion of soybean meal and bran is 2 ： 3, the moistening level is 120%, the raw material degeneration time is 20 rain and koji-making temperature is 30 ＂C. Under these conditions, the mature speed of spores is increased markedly; the white mycelium is thick and solid, the taste of koji is rich and with unique aroma; the activity of protease and amylase is higher, and best for koji fermentation.