基于不同力模型下的乌龙茶造型过程中理化与香气品质的变化

为了深入探明颗粒形乌龙茶造型过程典型造型力的作用效果及其对乌龙茶品质形成的影响,本文设计了搓揉力+压力模型(A)和纯压力模型(B)两种力模型,研究在制叶的力学特性、微观形态、生化成分以及毛茶色泽、香气品质的影响。结果表明:两种力模型在制叶最大应力及最大应变均值达到显著差异(p<0.05);两种力模型在制叶主要生化成分总体均呈下降趋势,毛茶的茶多酚、氨基酸、咖啡碱、黄酮含量差异显著(p<0.05);色泽方面,搓揉力与压力模型的毛茶中叶绿素a、叶绿素b含量均高于纯压力模型,干茶色泽也更偏绿明亮;香气方面,具花果香特征的罗勒烯、(Z)-己酸-3-己烯酯、丁酸丁酯、芳樟醇在搓揉力与压力模型中相对含量较高;感官审评中搓揉力+压力模型的毛茶品质综合表现优于纯压力模型。

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.