鲟鱼中荧光假单胞菌生长预测模型构建及货架期预测

为快速预测有氧贮藏鲟鱼的货架期、预防鱼肉变质，通过将鲟鱼有氧冰藏条件下的特定腐败菌（荧光假单胞菌）接种于灭菌鲟鱼片后置于0、4、10、15、20 ℃有氧贮藏，分析其生长动态及货架期终点的感官评分、pH值和挥发性盐基氮值，在以修正的Gompertz方程为一级模型的基础上，分别以平方根方程和Arrhenius方程为二级模型，建立并验证荧光假单胞菌的生长预测模型。结果显示：荧光假单胞菌菌数的最小腐败值为（7.35±0.05）（lg（CFU/g））；同时，分别在8 ℃和波动温度条件下对模型验证的结果表明：基于平方根方程的荧光假单胞菌生长预测模型的残差分布在－0.09～0.10之间，准确度Af为1.14、1.17，偏差度Bf为0.97、1.02，货架期预测相对误差为－7.95%、－3.28%；而基于Arrhenius方程的模型误差较大，其中残差分布在－0.17～0.24之间，Af为1.21、1.31，Bf为0.94、1.08，货架期预测相对误差为24.87%、7.54%。因此，基于平方根方程建立的模型可以更有效地预测有氧包装鲟鱼在0～20 ℃贮藏温度条件下的荧光假单胞菌的生长及相应货架期。

Predictive Modeling of Pseudomonas fluorescens Growth and Shelf Life Prediction of Sturgeon

The aim of this study was to establish predictive models for the growth of Pseudomonas fluorescens in sturgeon
and its shelf life. Pseudomonas fluorescens, the special spoilage organism (SSO) of aerobically stored sturgeon, was
inoculated to sterile sturgeon fillets and stored aerobically at 0, 4, 10, 15 or 20 ℃. The models were developed based on
the data of kinetic growth of Pseudomonas fluorescens and sensory evaluation, pH, total volatile base nitrogen (TVBN) at
the end of the shelf life of sturgeon. On the basis of the modified Gompertz equation, square root equations and Arrhenius
equations were used as the secondary models to construct the prediction models of growth and shelf life for Pseudomonas
fluorescens. The results showed that the average logarithmic value of Pseudomonas fluorescens was (7.35 ± 0.05) lg (CFU/g)
at the end of shelf life. Meanwhile, the models were validated under isothermal (8 ℃) and non-isothermal conditions. The
residual errors, accuracy factors (Af), bias factors (Bf) and relative errors of shelf lives from the models based on square root
equations were －0.09–0.10, 1.14 and 1.17, 0.97 and 1.02, and －7.95% and －3.28%, respectively. In contrast, the residual
errors, Af, Bf, and relative errors of shelf lives from the models based on Arrhenius equation were －0.17–0.24, 1.21 and
1.31, 0.94 and 1.08, and 24.87% and 7.54%, respectively. In conclusion, the square root equation models were more effective
for predicting the growth of Pseudomonas fluorescens and the shelf lives of sturgeon stored aerobically at 0–20 ℃.