Physicochemical and Aroma Quality Changes of Oolong Tea in Modeling Process under Different Forces Models

In order to find out the effect of typical molding force of round oolong tea and its effect on the quality formation of oolong tea,two force models of rubbing force and pressure model(A)and pure pressure model(B)were designed to study the mechanical properties,microscopic morphology,biochemical composition,color of dry leaf and the aroma quality of oolong tea. The results showed that the two kinds of force models achieved significant differences in the maximum stress and the maximum strain of the leaf(p<0.05).During the modeling process,the two biomechanical components of the two force models all showed a decreasing trend,and the tea polyphenols,amino acids,caffeine and flavonoids were significantly different(p<0.05). In terms of color of dry tea,the content of chlorophyll a and chlorophyll b in A model was higher than that in B model,and the color of dry tea was more green and bright. In terms of aroma,the relatively high content of ocimene,hexanoic acid,3-hexenyl ester,(Z)-,butanoic acid,butyl ester,and linalool with a floral and fruity character in the kneading force and stress model. In the sensory evaluation,the gross performance of the A model was better than that of the B model.