康普茶直投式发酵剂的制备及其发酵性能的研究

Preparation of Kombucha directed vat set and its fermentation performance

中文关键词:  康普茶  直投式发酵剂  冻干保护剂  发酵饮料

英文关键词:Kombucha  directed vat set  cryoprotectant  fermented beverage

中文摘要:

      目的 制备菌种成分明确的康普茶直投式发酵剂, 并对其发酵性能进行探究。方法 通过测定菌株存活率筛选适用于发酵康普茶的巴氏醋杆菌、木醋杆菌、拜耳结合酵母的冻干保护剂, 再将冻干后的菌粉接种至红茶中发酵, 以前期开发的康普茶混菌发酵剂为对照, 通过测定康普茶发酵过程中糖类、乙醇、有机酸和感官等指标考察直投式发酵剂的发酵性能。结果 巴氏醋杆菌、木醋杆菌、拜耳结合酵母的最优冻干保护剂分别为30 g/100 mL的菊粉、20 g/100 mL的海藻糖、30 g/100 mL的海藻糖, 存活率分别为92.41%±1.33%、57.61%±2.29%、52.95%±1.67%。在康普茶发酵过程中, 直投式发酵剂与未冻干的混菌发酵剂发酵的康普茶在主要成分、电子舌评测结果及感官评分等均呈现相似的变化趋势。直投式发酵剂发酵后的康普茶中以酸味柔和兼具健康功效的葡萄糖酸和葡萄糖醛酸为主, 醋酸仅在第2 d检测到; 在发酵终点康普茶的乙醇含量符合饮料的标准。结论 直投式发酵剂与实验室前期获得的混菌发酵剂发酵的康普茶品质相当, 可以为康普茶直投式发酵剂的制备提供理论和技术支持。

英文摘要:

      Objective To prepare Kombucha directed vat set with clear strain composition, and investigate the fermentation performance of the directed starter culture. Methods The cryoprotectants for Acetobacter pasteurianus, Gluconacetobacter xylinus and Zygosaccharomyces bailii were screened by measuring the survival rates of the lyophilized microbial strains, then the lyophilized bacteria powder was inoculated into black tea for fermentation. Taking the previously developed Kombucha mixed bacteria starter as the control, the fermentation performance of the direct vat set was investigated by measuring the saccharide, ethanol, organic acid and sensory indexes in the fermentation process of Kombucha. Results The optimal lyophilized protector of Acetobacter pasteuris, Acetylacea acetobacterium and Zygosaccharomyces bailii was 30 g/100 mL inulin, 20 g/100 mL trehalose, and 30 g/100 mL trehalose, respectively. The survival rates were 92.41%±1.33%, 57.61%±2.29% and 52.95%±1.67%, respectively. Kombucha fermented by the directed vat set and non-lyophilized starters showed similar trends in terms of the main components, electronic tongue evaluation results and sensory scores, etc. Gluconic acid and glucuronic acid, which had mild acidity and health effects, were the main components of Kombucha tea fermented by directed vat set starter, and acetic acid was only detected on the second day; the ethanol content of Kombucha at the fermentation end point met the beverage standard. Conclusion The quality of Kombucha fermented by directed vat set starter is comparable to that of the mixed fermenters obtained in the pre-lab, which can provide theoretical and technical support for the preparation of directed vat set starter for Kombucha.