传统发酵豆酱发酵过程中养分动态及细菌多样性

Changes of Nutrition and Bacterial Diversity During Traditional Soypaste Fermentation

摘要:

以山东传统发酵豆酱作为研究对象, 测定了发酵不同阶段的总酸、可溶性糖、有机碳、粗蛋白、氨基酸态氮、主要挥发性产物等指标, 对样品中细菌进行PCR-DGGE分析, 探讨了传统发酵豆酱中养分动态及细菌多样性。结果表明发酵过程中总酸含量先上升后下降而后又上升, 最后成品酱中为6.26%; 有机碳和可溶性糖含量都逐渐减少; 粗蛋白相对含量先略有平稳上升后下降; 氨基酸态氮含量一直在增加, 成品酱中为101.2 g/kg; 乳酸和甘油含量随发酵进程而增加, 成品酱中分别为5.65 g/kg和14.72 g/kg。DGGE分析表明发酵15 d时细菌种类最多, 随后一部分逐渐消失, 种类趋于稳定, 最后成品酱中出现有几种明显的优势种, 主要包括：未培养细菌(Uncultured bacterium)、乳酸乳球菌(Lactococcus lactis)、地衣芽孢杆菌(Bacillus licheniformis)的近缘种。

Abstract:

Nutrient dynamics and bacterial diversity of traditional soypaste were analyzed and discussed with samples from Shandong province by nutrition and denaturing gel gradient electrophoresis (DGGE) analysis. The nutrition value was determined by following parameters: total acid, water-soluble carbohydrate (WSC), organic carbon (OC), crude protein (CP), amino-acid nitrogen and volatile products. Results showed that the total acid was increased at first, and decreased, and then increased again up to 6.26%. The contents of OC and WSC remained decline. As for CP, it was decreased after increased stable. The amino-acid nitrogen was kept increasing during the whole progress and its concentration was up to 101.2 g/kg in final soypaste. The concentration of lactic acid and glycerol were increased during the fermentation, and were up to 5.65 g/kg and 14.72 g/kg in final soypaste, respectively. DGGE analysis indicated that there were the most kinds of bacteria in 15d soypaste, and then some of bacteria were disappeared gradually. Uncultured bacterium, Lactococcus lactis and Bacillus licheniformis of final soypaste were predominant species in final soypaste.