酱油发酵前期微生物变化及其主要香味物质分析

Analysis of microorganisms and main flavor substance in first stage of soy sauce fermentation

以传统工艺制作的酱油,在自然发酵的环境中接入纯培养的米曲霉与鲁氏接合酵母,利用稀释平板计数法,研究其发酵过程中霉菌、酵母菌和乳酸菌数量的变化,通过气相色谱法进行呈味物质的分析。试验发现,霉菌的数目在发酵过程中呈逐渐下降的趋势;乳酸菌和酵母菌在酱油发酵初始阶段数量较少,分别为1.2×103CFU/g和7.6×102CFU/g,随着发酵时间的延长,菌数急速增加,在发酵6、7 d达到最高值,数量分别为2.4×108CFU/g和3.2×106CFU/g,此后数量逐渐下降,在第15天降到103CFU/g左右时,数量不再随时间变化;酱油的呈味物质中含有愈创木酚,其含量在发酵28 d后达到所有呈味物质的0.136 5%。

With the traditional processing of soy sauce, and incubated with pure culture of Aspergillus oryzae and Zygosaccharomyces rouxii, the soy sauce was fermented at natural fermentation. The analysis of fungi, yeast and lactic acid bacteria＇s number had been ap plied with dilution plate counting methods, and the flavor substance was extracted with anhydrous ether and analyzed by gas chromatogram. Our results showing that the quantity of fungi decreased along fermentation time, the number of yeast and lactic acid bacteria at fermentation beginning is 1. 2 ×10^3 CFU/g and 7. 6×10^2 CFU/g respectively, from then on, the number of them increased quickly to 2.4×10^8 CFU/g and 3. 2×10^6 CFU/g at 6 and 7 days, after that point, they decreased gradually but stayed at 10^3 CFU/g from 15 days. Guaiacol was found in flavor substance, its content in flavor substance was 0. 136 5% after 28 days fermentation.