基于风味改善的食醋自吸式半连续酿造工艺优化

采用自吸式发酵罐液态深层半连续法发酵食醋,该方法生产效率高、生产周期短,但食醋风味不足。在传统液态法食醋发酵工艺基础上,通过筛选原料、添加糖化曲和多菌协同酒精发酵,可以提高食醋不挥发酸的含量,改善食醋风味。研究结果表明:以小麦为原料调浆液化完成后,加入6.5%(质量分数)增香糖化曲,35℃保温糖化1 h,接种5%(体积分数)乳酸菌与0.28 g/100 m L酵母菌共同酒精发酵,控制温度32℃发酵4 d,最后接种醋酸菌。将该工艺应用在摇瓶水平上液态法发酵食醋,得到的食醋中不挥发酸含量可达0.47 g/100 m L。将该工艺应用于5 L自吸罐液态半连续发酵得到的食醋成品,总酸度≥6 g/100 m L,不挥发酸含量≥0.5 g/100 m L,达到了国标对固态醋不挥发酸含量的要求。

Optimization of Self-Suction Semi-Continuous Vinegar Fermentation for Flavor Improvement

Semi-continuous submerged vinegar fermentation in a self-suction fermentor has the advantages of high production efficiency and short production cycle. However, the taste of the produced vinegar is not as good as desired. For increased non-volatile acid content and improved vinegar flavor, the traditional liquid-state fermentation process for vinegar production was modified by raw material selection, addition of saccharification agent and mixed-culture alcoholic fermentation. The vinegar production process was determined as follows: After addition of water, ground wheat was liquefied and saccharified by addition of 6.5% (m/m) flavor-enhancing saccharification agent at 35 ℃ for 1 h; afterwards, the substrate was inoculated with a mixture of 5% (V/V) lactic acid bacteria and 0.28 g/100 mL yeast, fermented at 32 ℃ for 4 d, and finally inoculated with acetic acid bacteria. The liquid-state fermentation carried out in shaking flasks yielded a product containing 0.47 g/100 mL non-volatile acids. The total acidity of vinegar produced in a 5 L self-suction fermentor by the semi-continuous submerged fermentation process was no less than 6 g/100 mL, and the volatile acid content was no less than 0.5 g/100 mL, both of which reached the requirements of the Chinese national standard.