[关键词]
[摘要]
酚类物质是草莓中重要的生物活性成分,具有不稳定易降解的特点。为探究草莓脯酚类物质在贮藏过程中的变化规律,研究了4、25和37 ℃贮藏温度下,不同包装的草莓脯中酚类物质的降解动力学。结果表明:草莓脯中的酚类物质对热和光不稳定,随贮藏温度的升高,降解速率增大,半衰期减小;同一贮藏温度下,真空避光包装的降解速率最慢,其次是真空透光、非真空避光和非真空透光。四种包装方式下草莓脯中酚类物质的降解均符合一级动力学模型,其反应活化能分别为22.45、17.75、18.91和17.42 kJ/mol。四种包装材料预测模型的验证值与实测值的相关系数R2>0.99,表明了模型的有效性,可用于预测任意温度下贮藏的酚类物质含量及草莓脯货架期。同时对草莓脯中酚类物质的热力学参数值进行了计算分析,为阐释酚类物质降解机制提供了依据。
[Key word]
[Abstract]
Phenolic substances are important bioactive components in strawberries, which are unstable and easy to degrade. In order to explore the changing trend of the phenolic substances in dried strawberries during storage, the degradation kinetics of these compounds in the dried strawberries stored in different packages at 4, 20and 37 ℃ were examined. The results showed that the phenolic substances in dried strawberry were unstable to heat and light. With the increase of storage temperature, the degradation rate increased and the half-life decreased. At the same storage temperature, the degradation rate of the strawberries in vacuum light-proof packaging was the lowest, followed by those with vacuum light-transmitting packaging, non-vacuum light-proof packaging and non-vacuum light-transmitting packaging. The degradation of phenolic substances in the dried strawberries packaged with the four packagings all conformed to the first-order kinetic model, with their reaction activation energies as 22.45, 17.75, 18.91 and 17.42 kJ/mol, respectively. The correlation coefficients between the validated values of the strawberries in the four packaging materials obtained from the prediction model and the measured values, R2, were higher than 0.99, indicating the effectiveness of the model. The model can be used to predict the contents of phenolic substances stored at any temperature and the shelf life of dried strawberries. At the same time, the values of the thermodynamic parameters for the phenolic substances in the dried strawberries were calculated and analyzed, which provide a basis for explaining the degradation mechanism of phenolics.
[中图分类号]
[基金项目]
江苏省重点研发计划项目(BE2021316)