盐水浓度及pH对高盐稀态酱油酿造初期酱醪理化性质影响的研究

本文以高盐稀态酱油为研究对象,分析了不同盐水浓度及pH值对其酿造前30 d酱醪理化特性的影响.结果表明:在自然pH(7.2),盐水浓度为16%、20%、24%条件下,随着盐水浓度的增加,酱醪中总氮、氨基酸态氮、总酸的增加速率以及pH值下降速率均减小耳还原糖含量增加.酿造30 d时,16%和20%盐水浓度的酱醪总氮相比2...

Effects of Brine Salt Concentration and pH on Physicochemical Properties during the early Fermentation of High-Salt Diluted Soy Sauce

The objective of this paper was to investigate the effect of salt concentration(SC) and pH of brine on physicochemical properties of moromi during the early 30-day fermentation for high-salt diluted soy sauce.The results showed that the increase rates of total nitrogen(TN),amino acid nitrogen(AN) and total acid and the decline rate of pH were decreased,while the reducing sugar content(as glucose) increased with the increase of SC at the natural pH.TN and AN in moromi with SC of 16% and 20% were increased by 5% and 7%,12% and 11% compared to those with 24% of SC,while the reducing sugar content in moromi with SC of 20% and 24% increased by 20% and 53% compared to that with SC of 16%.At the conditions of SC at 16%,TN in moromi didn’t change significantly and the decline rate of pH became slow when the pH of SC was adjusted from 7.2 to 8.5 and 9.5.After 30 days of fermentation,pH of moromi with original pH 9.5 became 5.04.At the 30 days of fermentation,the AN in moromi at pH8.5 and 9.5 increased by 12% and 4% compared to that in the natural pH.In the first 15 days of fermentation,there was no significant change in reducing sugar content,whereas the higher pH caused a decrease in the reducing sugar content at 30 days of fermentation.Therefore,reducing the SC and increasing pH might improve utilization of raw materials and amino acid conversion rate by adjusting the effects of protease activity and osmotic pressure.