Express Assessment Method for Color Characteristics of Cocoa-Containing Food Systems

Abstract

In the contemporary context, climatic conditions in cocoa bean-producing countries and disrupted logistics chains due to the coronavirus pandemic complicate stable cocoa products supply. The study aimed at developing an express assessment method for color characteristics of cocoa-containing food systems where cocoa powder replaced with brown pigment melanin obtained from buckwheat husks, partially. A man prepared five confectionery glaze prototypes: one based on non-alkalized cocoa powder and four samples containing 3; 5; 7 and 10 % melanin powder as a substitute for cocoa powder. The confectionery glaze based on alkalized cocoa powder served as a comparison sample. To study the glaze color characteristics, the researchers covered white plates with samples, enabled the glaze to harden, and then, took images of the glaze surface using a digital camera in a white box at a color temperature of 6000 K; processed images using image analysis software that provided color coordinates determination of any point of the uploaded image in the RGB model. Then, a man determined the color coordinates in trichromatic XYZ coordinates using a color converter. The results revealed that the confectionery glaze prototype containing 15% non-alkalized cocoa powder and 10% melanin was close to the control sample in terms of color characteristics. The suggested approach advantages are the expensive equipment absence, simplicity and data processing accessibility. The method enables running an objective color assessment of a cocoa-containing product, comparing product samples with each other, and defining color differences. The research results offer the challenges for the color scales development for cocoa-containing foods quality assessment.