乳酸菌的抗冷冻性及耐受机理

Anti-freezing Property and Mechanism of Lactic Acid Bacteria

摘要:

乳酸菌发酵剂在工业生产过程中, 会受到冷冻的刺激, 如真空冷冻干燥及后期的低温保藏, 此外, 发酵乳制品的保藏和干酪的成熟过程也都在低温中进行。这些均会对乳酸菌发酵剂及发酵乳制品质量产生一定的影响。因此, 掌握乳酸菌在冷冻条件下的反应机理有助于优化发酵剂和发酵乳制品在工业生产中的冷冻、发酵和贮藏条件, 从而提高产品质量和生产效益。本文对乳酸菌的抗冷冻性及机理进行了分析, 并对发酵剂的保护提出具体措施。

Abstract:

During industrial production of starters, Lactic Acid Bacteria are subjected to cold shock by preservative techniques like freezing, frozen storage, and vacuum freeze-drying. Moreover, starters subjected to these pressures need to function effectively during application at low temperature used in the perservation of fermented foods and curing of cheese. All of these factors can influence the quality of starter culture and its fermented foods to some extent. The survival and physiological conditions of the starter bacteria preserved by such techniques (freezing, frozen storage, and lyphilization) will determine their functionality in such applications. Therefore, a better understanding of the responses and mechanisms of Lactic Acid Bacteria under low temperatures and freezing may contribute to the protection of freezing, fermentation and storage for starter culture and fermented foods when they are suffered in low temperature processes. In this study, the protective mechanisms needed for starter bacteria to survive in above mentioned preservative techniques with good functionality were analyzed. Based on these analyses, we have proposed protection methods that would improve the functionality of starter bacteria preserved by freezing, frozen storage and/or lyophilization.