水分活度对碧螺春绿茶贮存稳定性的影响

The Effect of Water Activity on Stability of Green Tea during Storage

以碧螺春绿茶为实验材料,研究水分活度对绿茶贮存稳定性的影响。结果表明,水分活度对绿茶的贮存稳定性有很大的影响。不同水分活度下贮存4个月后,在高水分活度区域,绿茶的稳定性显著下降,各生化成分含量迅速降低。在低水分活度区域,碧螺春茶相对稳定,但脂质、咖啡碱、儿茶酚等成分含量的保留值小于Aw0.33处。碧螺春绿茶在Aw0.2～0.3范围内(单层水分含量对应范围)具有最佳稳定性。

The effect of water activity on the stability of green tea during storage was studied in this manuscript.The Guggenheim-Anderson-de Boer(GAB) equation was applied to model experimental data for moisture content as a function of water activity,and to calculate the monolayer moisture content,where the oxidative reactions are expected to be at minimum.Estimated monolayer moisture content was approximately 3.5%.It was concluded that the rate of ingredients in green tea were at minimum over the water activity range 0.2~0.3.High water activity could accelerated the degradation of green tea.