关键词: 高盐稀态酱油, 相容性溶质, 甘氨酸甜菜碱, 复合纤维素酶, 蛋白质转化率, 发酵周期

Abstract: The microorganisms and inherent or exogenous enzymes have very low activity because of high osmotic pressure during the traditional fermentation of high-salt liquid state soy sauce, which results in a low conversion rate of raw materials and a prolonged fermentation period. Glycine betaine is one of the compatible solutes synthesized by microorganisms under high osmotic pressure which protects the microorganisms and enzymes. In this study, glycine betaine was used added at different time points (0 d or 30 d) in the fermentation of high-salt liquid state soy sauce to protect microorganisms and external complex cellulase. The results showed that simultaneous addition of 0.20% or 0.30% glycine betaine and 0.15% complex cellulose (105 EGu/100 g sauce mash) before and after 30 d soy sauce fermentation obviously improved protein conversion rate by 2.26%－7.92%. Glycine betaine improved the quality of soy sauce effectively, and shortened the fermentation period by about15 d. Average protein conversion rate was increased by 3.17% when adding glycine betaine and complex cellulase after 30 d fermentation than before the beginning of fermentation.

Key words: high-salt liquid state soy sauce, compatible solutes, glycine betaine, complex cellulase, protein conversion rate, fermentation period