液态发酵麸醋工艺优化及其风味品质研究

Optimizing Production of Liquid-State Fermented Bran Vinegar and Study on Its Quality of Flavor

摘要:

为提高液态发酵食醋品质，在其传统工艺基础上添加麸皮浸出液，以四川麸醋醋醅中筛选的优良巴氏醋酸菌为菌种，根据单因素实验确定影响醋酸发酵的显著因素，并通过Box-Behnken设计试验优化，其最优发酵条件为：麸曲添加质量分数1.11%、醋酸菌接种体积分数13.71%、醋酸发酵温度31.50 ℃，在此条件下产酸量为68.48 g/L。以四川某醋厂生产的液态发酵食醋为对照，对所得液态发酵麸醋进行感官评价、挥发性成分和游离氨基酸分析。液态发酵麸醋口感柔和、香味独特，检测出20种挥发性成分、17种游离氨基酸；游离氨基酸总量为805.29 mg/dL，各项指标均优于液态发酵食醋，品质明显提升。

Abstract:

In order to improve the quality of liquid-state fermented vinegar，based on the traditional techniques，bran leachate was added into fermentation system，and Acetobacter pasteurianus isolated from the normal grains of Sichuan bran vinegar was inoculated. The significant factors which influence acetic acid fermentation were confirmed by single factor experiment，then the fermentation process was optimized by response surface methodology designed by Box-Behnken principle. The optimum fermentation conditions were as follows：the addition quantity of bran koji was 1.11%，the inocula biomass acetic acid bacteria was 13.71%，fermentation temperature was 31.5 ℃. Under these conditions，the acid production reached 68.48 g/L. Using liquid vinegar obtained from one factory at Sichuan as a control，the quality of liquid-state fermented bran vinegar was estimated with sensory evaluation，volatile constituents and free amino acid indexes. The results showed that the liquid-state fermented bran vinegar possessed pure taste and unique aroma. 20 volatile components and 17 free amino acids were identified in the liquid-state fermented bran vinegar. The total content of free amino acids was 805.29 mg/dL. Quality of liquid-state fermented bran vinegar was significantly improved.