2种米曲霉发酵酱油风味物质比较

Comparison of Flavor Compounds in Soy Sauces Fermented by Two Aspergillus oryzae Strains

为进一步比较传统菌株米曲霉沪酿3.042和前期实验诱变菌株米曲霉100-8酿造酱油的差异。通过高效液相色谱、气相色谱-质谱联用仪比较酱油中有机酸、氨基酸和风味物质成分的差异。通过发酵终期酱油有机酸的结果比较发现:米曲霉100-8发酵的酱油中苹果酸含量增加,柠檬酸和琥珀酸含量下降。通过酱油发酵在大曲阶段和后期阶段的氨基酸比较发现,使用米曲霉100-8菌株发酵的酱油大曲及其后期发酵为酱油阶段,天冬氨酸、谷氨酸和精氨酸这3种氨基酸含量都明显升高。这些有机酸和氨基酸含量之间比例的差异性是造成酱油风味不同的原因之一。对风味物质成分的分析发现:与对照相比,米曲霉100-8发酵的酱油中醇、醛、酸和吡嗪类物质都有所增加,其中风味物质增多最明显的是吡嗪类。通过米曲霉100-8酿造的酱油与传统米曲霉沪酿3.042比较,其有机酸、氨基酸和风味物质都有明显的不同。

The contents of organic acids, amino acids and flavor components in soy sauce fermented by Aspergillus oryzae 3.042 were analyzed by high performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS) in comparison to those of soy sauce fermented by A. oryzae 100-8, a mutant strain. The organic acids, amino acids and flavor components at the end of low-salt solid soy sauce fermentation by A. oryzae 3.042 and 100-8 strains were measured. The content of malic acid in soy paste fermented by A. oryzae 100-8 was increased, while citric acid and succinate were decreased. The contents of asparagic acid, glutamic acid and arginine were increased in fermented koji and soy sauce. The taste of soy sauce was also influenced by different ratios between organic acids and amino acids. The contents of alcohols, aldehydes, acids and pyrazines in soy sauce fermented by A. oryzae 100-8 were enhanced. More pyrazines were detected in soy paste fermented by A. oryzae 100-8. These results seem to provide a theoretical basis for the soy sauce industry.