真空包装鸡肉早餐肠货架期预测模型的建立

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

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。

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/tm^x （maximum specific growth rate） and 2 （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 ℃.