Abstract: Melanin is a kind of complex polymeric phenolic compound, which can be used in the field of medicine, cosmetics, food and electron. In this work, melanin was extracted from apricot kernel skin by alkaline extraction, acid hydrolysis, and repeated precipitation, and one-factor-at-a-time and orthogonal array design methods were used to optimize four extraction conditions including NaOH concentration, extraction temperature, extraction time and material-to-liquid ratio based on melanin yield. Three extraction conditions except extraction time had a highly significant effect on melanin yield (P ＜ 0.01), and could be ranked in descending order of importance as follows: extraction temperature ＞ NaOH concentration ＞ material-to-liquid ratio. The optimal extraction conditions were NaOH concentration of 0.4 mol/L, extraction temperature of 80 ℃, and extraction duration of 6 h, and material-to-liquid ratio of 1:20. Under these conditions, the yield of melanin was 7.2%.

Key words: apricot kernel skin, melanin, extraction process