真空包装鸡肉早餐肠货架期预测模型的建立

为研究低温肉制品的货架期预测模型，选取真空包装的鸡肉早餐肠为研究对象，通过测定4 ℃贮藏温度条件下早餐肠细菌总数及感官、理化指标变化情况，确定早餐肠最小腐败量为6.49（lg（CFU/g））。同时测定2、6、10、15 ℃条件下的细菌总数变化情况，运用Baranyi模型拟合细菌总数在鸡肉早餐肠中的生长动力学模型，回归系数R2均在0.99以上。应用平方根模型拟合温度对生长动力学模型参数的影响，模型呈现良好的线性关系，回归系数R2均大于0.97，且残差平方和均小于10－2，说明该预测模型的拟合优度较高。在确定早餐肠最小腐败量与生长预测模型的基础上，建立了鸡肉早餐肠的货架期预测模型，预测值与实测值的相对均误差值均在1 d上下浮动，表明建立的模型能够快速准确的预测2～15 ℃贮藏条件下鸡肉早餐肠的货架期。

Establishment of Prediction Model for the Shelf-life of Vacuum-Packaged Chicken Breakfast Sausage

In order to develop a predictive model for the shelf-life of vacuum-packaged chicken breakfast sausage, the
changes in total bacterial count, sensory and physicochemical index of samples stored at 4 ℃ were analyzed to determine
the average number of total bacterial count at the end of the shelf-life. Meanwhile, the bacterial growth in samples stored
at 2, 6, 10 and 15 ℃ was determined to fit Baranyi model and Belehradek (square root) model, respectively. Based on
these investigations, a predictive model for the shelf-life of vacuum-packaged chicken breakfast sausage was established.
Results showed that the average number of total bacterial count was 6.49 (lg (CFU/g)) at the end of the shelf-life. The
kinetic equations of total bacteria at four different temperatures were developed and the regression coefficients for all these 4
equations were higher than 0.99. The temperature dependence of the kinetic parameters μmax (maximum specific growth rate)
and λ (lag phase) was modeled using Belehradek (square root) model, and both equations showed good linear relationship. Their
residual sum of squares (RSS) were both lower than 10-2, showing the reliability of the models describing temperature dependence.
The small relative error between the predictive and actual shelf life, fluctuating around 1 d, indicated that the predictive model is
reliable for the shelf-life of vacuum-packaged chicken breakfast sausage stored at a temperature ranging from 2 to 15 ℃.