基于假单胞菌生长模型预测冷却牛肉的货架期

假单胞菌（Pseudomonas spp.）的生长繁殖是影响冷却牛肉货架期的重要因素。为确定假单胞菌为冷却牛肉的特定腐败菌并建立其货架期预测模型，将屠宰后的冷却牛肉4 ℃贮藏，测定了假单胞菌数量与菌落总数、挥发性氨基氮（TVBN）值、颜色明度值（L*）及感官评定分值等品质指标，并确定了冷却牛肉的假单胞菌腐败限控量。将冷却牛肉分别置于0 ℃、5 ℃、10 ℃、15 ℃、20 ℃和25 ℃条件下进行假单胞菌计数，建立Gompertz方程的初级生长模型和二级模型，并进行了模型的验证，建立了货架期预测模型。研究表明，Gompertz预测模型能有效预测4～25 ℃条件下假单胞菌在冷却牛肉中的生长情况，在0 ℃、5 ℃和10 ℃温度条件下，对牛肉货架期进行验证，与实际货架期相比偏差＜1 d，表明货架期预测模型适用。

Prediction of shelf life of chilled beef base on Pseudomonas spp. growth model

The growth of Pseudomonas spp. is the important factors affecting the shelf life of chilled beef. In order to determine the Pseudomonas spp. as specific spoilage organisms of cool beef, the shelf life prediction model was established. Chilled beef after slaughter was storage at 4 ℃, the number of Pseudomonas spp., total number of bacterial colony, total volatile basic nitrogen (TVBN) value, chromatic aberration L* value, sensory score and other quality indicators were determined, and the corruption control quantity of Pseudomonas spp. in chilled beef were determined. The number of Pseudomonas spp. in chilled beef stored at 0 ℃, 5 ℃, 10 ℃, 15 ℃, 20 ℃ and 25 ℃ was counted respectively. The primary growth model and the secondary model of Gompertz equation were established and verified, and the shelf life prediction model was established. The results showed that Gompertz prediction model could effectively predict the growth situation of Pseudomonas spp. in chilled beef stored at 4-25 ℃. Under the conditions of 0 ℃, 5 ℃ and 10 ℃, the prediction shelf life was less than 1 d compared to the actual shelf life, which indicated that shelf life prediction model was applicable.