Relationship Between Color Evaluation and Chlorophyllian Pigment Content in Dried Parsley Leaves

Tristimulus calorimetry was used as an analytical method for evaluating the color of different dehydrated parsley samples. The trichromatic data were expressed in the two CIE systems: X, Y, Z, and L* a* b*. The hue function tan −1 b*/a* was highly correlated with visual ranking (r =+0.979) and residual chlorophyll content (r =+0.973). Relating X, Y, and 2 to visual score and pigment determination through simple and multiple regressions also demonstrated good correlations, X and Y being preponderant variables. These correlations provide a fast method to measure the degree of chlorophyll degradation and color quality of parsley leaves during drying and storage. Simple linear regression equations were used to estimate the color of 13 samples of fresh parsley, previously dehydrated in a pilot warm air dryer under different conditions.