Zhenying Liu

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3. Results 3.1. Colorimetric Analysis The color parameters of honeysuckle samples were determined by using the colorimeter combined with the CIE color space system which is widely used in the food [41,42] and herbal medicine [43,44] industries. As shown in Figure 2, the measured L*, a*, b*, C*, h*, and calculated ΔE values were combined to draw a heat map and analyzed with a PCA score. There was an obvious difference between differently colored samples.