经真空冷冻干燥得到的乳酸菌发酵剂存活率和后期的低温贮藏稳定性与诸多因素相关.本文综述了制备乳酸菌发酵剂过程中高密度发酵和真空冷冻干燥工艺的不同对乳酸菌抗冷冻性的影响,其中高密度发酵过程中的培养基组分、培养温度、发酵恒定pH、中和剂的选择、菌体收获时期和发酵结束后处理以及真空冷冻干燥过程中保护剂的添加、预冷冻处理等是影响乳酸菌抗冷冻性的重要因素.通过对这些相关因素的综述分析,为提高乳酸菌发酵剂的冻干存活率和后期的低温贮藏稳定性提供新的思路,且应用抗冷冻性强、活力高的乳酸菌发酵剂对有效提高乳制品的质量和企业的经济效益意义重大.%The survival rate and low temperature stability of lactic acid bacterial starter obtained by vacuum freeze-drying are governed by several factors. In this paper, the influence of the technology of high cell density cultivation and vacuum freeze-drying on cryotolerance of lactic acid bacteria for use as starters was analyzed. During fermentation, the following factors had a significant effect on the cryosurvival of lactic acid bacteria: culture medium, temperature control, pH stat, the neutralizer used, the harvesting stage of the cell crop, and post-fermentation handling of the concentrated cells. Factors affecting cell viability subjected to lyophilization include the following: cryoprotectants used, conditions used in initial freezing of the cell concentrate, and during vacuum freeze-drying. A good understanding of these factors will provide a reliable technology for preserving high cell density starter. The use of starter bacteria with high cryotolerance and viability can improve the quality of fermented milk products and boost economic benefits to the dairy industry.
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