自然冷却与真空冷却对蛋糕货架期的影响

Effect of Natural Air Cooling and Vacuum Pre-cooling on Shelf Life of Cake

为考察冷却方法对蛋糕货架期的影响,进行了自然冷却与真空冷却蛋糕的实验研究。比较了经两种方法冷却后,在不同贮藏温度条件(4℃、15℃、25℃、37℃)下,微生物随贮藏时间的变化规律。发现微生物数量随贮藏时间的延长而增加,微生物生长速率随贮藏温度的升高而增大。根据不同贮藏温度条件下蛋糕中微生物随时间的变化,拟合得到微生物生长的动力学初级模型。并运用Arrhenius方程分别建立了蛋糕真空冷却后贮藏过程中菌落总数、霉菌数量与贮藏温度、时间之间动力学二级模型。结合动力学模型,推导出了真空冷却蛋糕的货架期预测模型。研究结果表明,所建立的蛋糕货架期预测模型其预测误差小于12%,可用于预测蛋糕的货架期。

The influence of vacuum pre-cooling cake on the shelf life was analyzed and compared with natural air cooling.The changes of total number of bacteria and moulds in cakes during storage at different temperatures（4℃,15℃,25℃,37℃） were analyzed.Results showed that the total microbial count of cake was increased with prolonged storage time,and there was an increase in microbial growth rate as storage temperature rose.Primary kinetic models were obtained by analyzing the changes of microbial count in cakes.Kinetic models were developed for total number of colonies and moulds as a function of storage time and temperature based on Arrhenius equation.Mathematic models for predicting the shelf life of cake were obtained based on the kinetic models.It shows that relative error between prediction by the model for the shelf life of cake and observed shelf life is less than 12%,which indicates that this model could be used for predicting the shelf life of cakes.