微生物共培养强化技术对郫县豆瓣酱陈酿过程中挥发性组分变化规律的研究

Effect of Microbial Co-culture on Volatile Compounds of Pixian Bean Paste during Fermentation Period

不同种属耐盐酵母和乳酸菌组合应用于郫县豆瓣酱陈酿,研究其对陈酿过程中主要理化指标及风味组分变化规律的影响。研究结果表明:不同组合的微生物菌群均改变了陈酿过程中酱醅的总酸、氨基态氮、还原糖和总酯等主要理化指标,陈酿120天后,其总酸、氨基态氮的差异不显著,还原糖因菌种组合方式及培养方式不同而异,此外,总酯显著增加。检出的86种挥发性组分中,强化后其酯类和酚类组分呈单调增。酯类组分中贡献较大的是己酸乙酯、苯乙酸乙酯和乙酸乙酯等组分。同时强化后,对甲氧基苯酚、4-EP、卡必醇、芳樟醇、紫罗酮、苯甲酮等组分的含量也有所增加。

In this study, effects of halotolerant yeasts and lactic acid bacteria on physiochemical prop- erties and volatile compounds of Pixian bean paste are investigated by using lactic acid bacteria and yeasts as starter cultures during the fermentation period of bean paste. The results show that the addition of different kinds of microorganisms can alter the physiochemical properties of Pixian bean paste,such as total acid of moromi, ammoniacal nitrogen, reducing sugar and total esters. After being fermented for 120 days, no obvious changes are observed in total acids and ammoniacal nitrogen, while the content of reducing sugar changes with the combination patterns and cultivation modes of strains. A total 89 kinds of volatile compounds are identified based on HS-SPME/GC-MS analysis. The contents of esters and aromatic compounds detected in inoculated samples increase significantly compared with those in control samples. As for esters, ethyl caproate, ethyl phenylacetate and ethyl acetic ester exhibit the highest contents. In addition, exogenous lactic acid bacteria and yeasts enhance the contents of methoxyphenol, 4-EP, carbitol, linalool, ionone and phenyl ketone.