冷藏三文鱼片微生物生长动力学模型适用性分析及货架期模型的建立

Applicability Analysis of Microbial Growth Dynamics Models and Establishment of Shelf-life Model for Salmon Slices duing the Cold Storage

为研究不同冷藏温度(0,4,10℃)下三文鱼片中菌落总数、明亮发光杆菌、乳酸菌、假单胞菌以及产H2S细菌的生长情况,用不同的微生物生长动力学模型对其微生物生长动态进行非线性拟合,探究动力学模型对冷藏三文鱼片微生物生长的适用性,建立其剩余货架期模型。分别以一级化学反应动力学模型、修正的Gompetz模型、Baranyi and Roberts模型作为一级微生物生长动力学模型,描述微生物在恒定温度下随时间的生长规律;分别以Arrhenius方程和Belehradek方程(平方根模型)为二级模型,描述贮藏温度对微生物生长曲线的最大比生长速率(μmax)及延滞时间(λ)的影响。结果显示:Baranyi and Roberts模型方程能更好地描述冷藏三文鱼片中微生物的生长动态,拟合效果优于一级化学反应动力学模型和修正的Gompertz模型。Baranyi and Roberts模型方程所得参数用Belehradek方程拟合,结果发现冷藏三文鱼片微生物生长的最大比生长速率和延滞时间与贮藏温度呈良好的线性关系。由Belehradek方程建立的冷藏三文鱼片剩余货架期模型相对误差在(±18.90%)内,比Arrhenius方程建立的货架期预测模型预测更准确,可很好地描述菌落总数、假单胞菌、产H2S细菌及明亮发光杆菌随贮藏时间和温度的变化规律,预测冷藏三文鱼片的货架期。

The changes of total viable counts （TVC）, Photobacterium phosphoreum, lactic acid bacteria, pseu- domonas and H2S-producing bacteria in salmon slices at the different storage temperatures （0, 4, 10 ℃） were studied, and microbial growth was non-liner fitted by using different growth dynamic models, in order to explore the application effect of different microbial growth dynamic models for salmon and establish the remaining shelf-life model of cold stor- age salmon slices. The first-order chemical reaction kinetics model, the modified Gompetz model, Baranyi and Roberts model were used as the primary microorganism growth dynamics model respectively, to describe the microbiological growth at constant temperatures. Arrhenius equation and Belehradek equation （square root model） were used as secondary models to describe the influence of temperature on maximum specific growth rate （μmax） and lag phase （λ） of microbio- logical growth curve. The results showed that the model equation of Baranyi and Roberts could describe the dynamic mi- crobial growth in cold temperature salmon better and the fitting effect was superior to the first-order chemical reaction kinetics model and the modified Gompertz model. The parameters obtained by Baranyi and Roberts equation were fitted by Belehradek equation and the results showed that there were a good linear relationship among temperature, maximum specific growth rate and lag phase of microbial growth of salmon slices during the cold storage. And the remaining sheff- life model obtained by Belehradek equation was more accurately than that of Arrhenius equation for salmon slices. The relative-error of the established shelf-life model was within the scope of ±18.90%, which suggested that total viable counts, Photobacterium phosphoreum, lactic acid bacteria, pseudomonas and H2S-producing bacteria of salmon slices during cold storage could be described well by the relative shelf-life prediction models.