六堡茶茶汤色泽量化分析3种方法的比较

Comparative Study on Three Quantitative Analysis Methods for the Color Liupao Tea Infusion

为比较不同方法所得色泽参数的差异,探寻一种能够更加客观真实反映茶汤色泽的量化方法,选用36个六堡茶散茶样品为研究对象,分别采用3种不同方法提取茶汤的色泽参数,并对色泽参数进行模拟验证对比分析。结果表明,方法1基于Adobe Color CC和方法2基于Matlab的茶汤色泽量化分析方法所测定的不同茶样间色泽参数变化规律基本一致,而方法3直接采用台式色差仪所测定结果与方法1和方法2相比有明显差异,色泽参数相关性分析表明这些差异主要在于茶汤黄度值的变化不同。采用人工神经网络分析模型发现,上述3种方法所得色泽参数对汤色得分的预测准确度分别为86.1%、83.7%和63.8%。以实际茶汤色泽为参考,通过色泽参数模拟验证对比分析发现,基于计算机视觉的图像采集装置结合Adobe Color CC的茶汤色泽参数提取方法能够更加真实地反映出六堡茶茶汤的实际色泽,表明该方法有望为茶汤色泽的量化分析提供一种相对客观、准确的分析检测方法。

This study compared the difference in color parameters measured by different methods for tea infusion in order to explore a quantitative method that can reflect the color of tea infusion more objectively and truly.In total 36 Liupao tea samples were selected for preparation of tea infusions,and three different methods were used to extract color parameters from the tea infusions.The color parameters were simulated and verified for comparative analysis.The quantitative results of method 1 based on Adobe Color CC and method 2 based on Matlab for color parameters were generally consistent with each other,but significantly different from those of method 3(direct measurement with a bench-top colorimeter).Correlation analysis of color parameters revealed that the difference was mainly attributed to the yellowness value.The results of artificial neural network(ANN)modeling showed that the prediction accuracies of the three methods for color parameters were 86.1%,83.7%and 63.8%,respectively.The color parameter extraction method of image acquisition based on computer vision combined with Adobe Color CC could more truly reflect the actual color of Liupao tea,suggesting that this method provides a relatively objective and accurate detection method for the quantitative analysis of tea infusion color.