乳源嗜冷菌及其耐热蛋白酶对乳制品品质的影响OA

Psychrophilic bacteria can grow and reproduce at low temperatures ranging from 0 to 5℃and secrete large amounts of extracellular heat-resistant proteases,making them a major cause of spoilage and deterioration of raw milk and its products.Even after conventional heat treatment processes used in dairy production,some residual activity of these heat-resistant proteases remains.These residual proteases continuously break down casein in milk and act synergistically with lipases,leading to quality issues such as bitterness,coagulation,and stratification in dairy products,thereby shortening their shelf life.This paper systematically reviewed the definition,bacterial classification,and contamination pathways of lactobacillus-derived psychrophilic bacteria,and elaborates on the classification,thermostable characteristics,and mechanism of action of proteases on dairy product quality.At the same time,it summarized the current application status of mainstream detection methods for thermostable proteases(Folin-Phenol method,ELISA method)and quantitative and qualitative detection techniques for psychrophilic bacteria(traditional plate culture method,PCR,low cytometry,third-generation gene sequencing technology),and compares the technical advantages and limitations of each method.In addition,this study combined the latest technological progress and from three dimensions of source control,precise detection,and inhibition of residual heat-resistant protease activity,looks forward to future research priorities,in order to provide theoretical basis and practical technical support for the dairy industry to achieve efficient and precise control of psychrophilic bacteria and thermostable proteases,product quality upgrade,and stable shelf life guarantee.