Effects of Different Storage Conditions on Shelf Quality of Flat Green Tea

According to the common industry difficulties that green tea was easily aging and deterioration during storage, the conditions of temperature, humidity, oxygen and moisture were used as control variables to investigate the storage quality stability of green tea. Based on the above, the optimal storage conditions that including the quality, flavor and nutritional value of green tea could be obtained. The storage quality control parameters of green tea were optimized through uniform design experiment combined with PCA (principal component analysis) and regression analysis. The results showed that the content of tea polyphenols and catechins decreased with the storage time, the ration of ester catechins and non ester catechins increased obviously after 6 months. However, the content of caffeine changed insignificantly. The optimal collaborative quality control parameters of green tea were temperature of 25 ℃, relative humidity of 55%, oxygen content of inner package of 0.2%, and the moisture content of 4.5%. Under these conditions, the sensory flavor and phytochemicals were most stable. In addition, the comprehensive scores of tea polyphenols, catechins and sensory scores were 1.28, 1.10 and 2.09, respectively. This study provides technical support and reference for the formulation of green tea storage, circulation and preservation control regulations.