4 ℃贮藏条件下酱牛肉品质的变化与货架期预测

Quality variations and shelf life prediction of sauced beef stored at 4 ℃

中文关键词:  酱牛肉  微生物生长  品质变化  预测模型  货架期

英文关键词:sauced beef  microbial growth  quality variation  predictive model  shelf life

中文摘要:

      目的 研究4 ℃冷藏条件下的酱牛肉细菌总数、理化指标变化及它们的相关性, 为客观评价酱牛肉的品质提供依据, 并为预测酱牛肉的货架期提供手段。方法 生理生化指标的测定、感官评价系统的建立参照国标方法, 通过修正的Gompertz方程构建了酱牛肉菌落总数生长的一级模型, 并对货架期进行预测分析。 结果 在4 ℃贮存条件下, 酱牛肉理化指标与细菌总数均随时间呈现动态变化, 其中色差a值、C*值均不断降低, 而挥发性盐基氮(total volatile base nitrogen, TVB-N)呈上升趋势。Pearson相关性分析发现细菌总数与TVB-N值最显著相关。通过验证预测值和实际值的差异, 表明该细菌总数的一级模型可以较好预测4 ℃冷藏过程中酱牛肉的细菌生长动态。结合感官评定结果, 构建该条件下的酱牛肉货架期预测模型为SL=λ? [(6.89?N0)/μmax×2.72]×{ln[?ln[(5.05?N0)/(6.89?N0)] ?1]}。结论 通过修正的Gompertz方程可以较好地拟合4 ℃温度条件下市售酱牛肉的品质变化, 通过酱牛肉初始菌数可以对4 ℃下市售酱牛肉的剩余货架期进行初步 预测。

英文摘要:

      Objective To study the total number of bacteria, physical and chemical indexes and their correlation of the sauced beef at 4 ℃, so as to provide a basis for the objective evaluation of the quality of the sauced beef and a means to predict the shelf life of the sauced beef. Methods The determination of quality indexes and establishment of sensory evaluation system were based on national methods. The modified Gompertz equation was used to construct a first-level model of total bacterial count in sauced beef and the prediction of shelf life was carried out. Results At the storage condition of 4 ℃, all the physical and chemical indexes of sauced beef and total number of bacteria dynamic changed, in which the values of color a, C* decreased while the total volatile basic nitrogen (TVB-N) increased. Pearson correlation analysis showed that total bacterial count was most significantly correlated with TVB-N value. The difference between predicted value and actual value was verified, indicating that the model was effective to predict the bacterial growth dynamics of sauced beef during 4 ℃ storage. Combined with sensory evaluation results, the shelf-life prediction model of sauced beef was SL=λ? [(6.89?N0)/μmax×2.72]×{ln[?ln[(5.05? N0)/(6.89?N0)]?1]}. Conclusion The modified Gompertz equation can better fit the quality change of sauced beef at 4 ℃, and the remaining shelf life of sauced beef can be predicted by initial bacterial count of sauce beef at 4 ℃.