Effects of Hair Dying by Used-up Coffee Grounds Extract (CGE)

Abstract

Purpose: This study aimed to examine the effects of hair dyeing employing used-up coffee grounds extract (CGE).Methods: The total polyphenol concentration of CGE was analyzed using the Folin─Ciocalteu’s method, and a shampoo formulation was prepared by adding different CGE concentrations. The hair dyeing effectiveness was observed according to changes in these two variables: dyeing concentration and dyeing time. To investigate the dyeing effects, L^* (Lightness), a^* (Red─Green), and b^* (Yellow─Blue) values were measured using a colorimeter. The optical density value was measured to examine the hair’s fading degree after bleaching.Results: The total polyphenol concentration in CGE was 122─133 mg GAE/g. The samples showed significant dyeing effects before and after application in terms of L^*, a^*, and b^* values. Hair dyeing ability increased with both amplified CGE concentration and dyeing time. Regarding the bleaching process, no decrease in hair colour intensity or change in hair’s fading degree was observed for 21 days.Conclusion: The possibility of dyeing using CGE has been demonstrated, and further commercialization as a shampoo formulation is considered possible.