预冷后宁夏菜心贮藏期内品质分析及货架期的预测

Quality Analysis and Shelf Life Prediction of Ningxia Cabbage during Storage after Precooling

采用真空预冷和冷库预冷两种方式对宁夏菜心进行处理,分别在0、5、10℃下进行预冷和贮藏保鲜实验,测定其贮藏期内失重率、叶绿素、色泽等品质指标,直到其失去食用价值,并建立动力学分析模型预测其货架期。结果表明,在预冷温度0、5、10℃条件下,菜心贮藏的温度越低,其品质指标变化越慢;真空预冷后,贮藏期内菜心品质优于冷库预冷,真空预冷可有效延缓其失重率、叶绿素和色泽的下降,0℃是宁夏菜心保持良好感官品质的最佳真空预冷和贮藏温度。通过动力学分析显示,失重率和L~*值、a~*值的变化符合零级反应动力学模型,叶绿素和b~*变化适合一级反应动力学;经验证所建立的动力学模型有效,可以用于预测贮藏温度0、5、10℃条件下,菜心的货架期分别为21、12、9 d。

Vacuum precooling and cold storage precooling were used to treat Ningxia cabbage.The precooling and storage experiments were carried out at 0,5 and 10℃,respectively.The weight loss rate,chlorophyll,color,and other quality indexes were measured during the storage period until it lost its edible value.A dynamic credit analysis model was established to predict its shelf life.The results showed that the lower the storage temperature was,the slower the change of quality index was.After vacuum precooling,the quality of cabbage was better than cold storage precooling.Vacuum precooling could effectively delay the decline of weight loss,chlorophyll,and color.0℃was the best vacuum precooling and storage temperature for maintaining good sensory quality of cabbage in Ningxia.The dynamic analysis showed that the changes of weight loss rate,L value and a value are in accordance with the zero-order reaction kinetic model,and the changes of chlorophyll and b were suitable for the first order reaction kinetic model.The dynamic model established was verified to be effective and could be used to predict the shelf life of vegetable heart under the storage temperature of 0,5 and 10℃for 21,12 and 9 d respectively.