摘要
Abstract
Box-Behnken experimental design and response surface methodology were employed to optimize the conditions for extraction of purple sweet potato peel pigment. Also, the effect of various physicochemical factors on the stability of the pigment was addressed. The optimum extraction conditions were obtained as follows:0.5%citric acid:anhydrous ethanol at a volume ratio of 1:1 as extraction solvent;solid-to-solvent ratio, 1:60 (g/mL);temperature, 50℃;and time, 20 min. Under these conditions, the predicted absorbance value of the pigment solution was 0.843 and the experimental value was 0.838. The pigment was unstable under light and strong alkali conditions (pH>7). It was relatively stable at temperatures between 4 and 60℃. Metal ions including K+, Ca2+, Na+, Zn2+, Mg2+, Cu2+, Mn2+, and Fe3+were helpful in the degradation of the pigment. Within the safe dosage range, its stability was hardly affected by benzoic acid, sorbic acid, citric acid, sucrose, soluble starch, glucose, and sodium chloride. Therefore, it can be used as food coloring agent.关键词
紫薯皮/色素/响应面法/稳定性Key words
purple sweet potato peel/pigment/response surface methodology/stability分类
轻工纺织
