采用自主研发的微滤膜偶联生物反应器制备泡菜用液体发酵剂,直接用于泡菜发酵。研究表明,通过生物反应器可控制乳酸菌培养过程中的pH、温度、溶氧量和追加营养物质的时间,植物乳杆菌在生物反应器内恒定pH培养12 h后活菌数达到5～8×109 CFU/mL;选择中空纤维膜膜滤的操作条件为蠕动泵转速50 r/min,压力0.15 MPa,对菌悬液进行膜滤浓缩1 h可得到4 L活菌数为2～3×1010 CFU/mL的浓缩菌液。浓缩菌液稀释5 000倍作为泡菜用发酵剂,直接用于泡菜发酵。室温条件下发酵3 d得到优质泡菜,比自然发酵短2 d。此微滤膜偶联生物反应器结构简单、使用方便、自动化程度高、适用于工业化大规模连续生产泡菜发酵剂。

In this paper,the bioreactor with micro-filtration membrane was developed and prepared for the liquid starter used directly for pickle fermentation.The results showed that,the pH,temperature,dissolved oxygen and time for nutrients addition could be controlled by this bioreactor and the viable cell concentrations of Lactobacillus plantarum reached(5~8)×109 CFU/mL with constant pH after 12 h.Under the optimum operation conditions of membrane filtration(the peristaltic pump speed 50 r/min and the pressure 0.15 MPa),the viable cells of the concentrated broth was about(2~3)×1010 CFU/mL,and the suspensions could be used as the starter after diluted by 5000-fold.Under room temperature,the high-quality pickle was obtained after 3 d,less than the natural fermentation of 2 d.With its simple structure,convenient use and high degree of automation,this bioreactor is suitable for continuous large scale industrial production of pickle fermentation.