흑미 미강으로부터 안토시아닌의 최적 추출 조건 및 안토시아닌 추출 분말의 저장 안정성

Black rice bran, a by-product from rice milling process, is a good natural source of anthocyanin pigment. The purpose of this study was to determine the optimum conditions for anthocyanin extraction from black rice bran as well as the stability of anthocyanin extract according to different storage temperatures. The main anthocyanin in ‘Heugkwang’ rice bran was identified as cyanidine-3-glucoside (C3G) by HPLC and LC-MS/MS. The yield and C3G content of black rice bran extract were investigated with various extraction solvents, temperatures, and times. The results indicate that the optimum extraction solvent, temperature, and time were 50% ethanol, 70°C, and 2 h, respectively. The stability of anthocyanin extract was studied during a storage period of 168 days at various temperatures (-20°C, 4°C, and room temperature). Hunters values (L, a, and b) of anthocyanin extract increased, whereas C3G content continuously decreased up to 168 days. Variations in Hunters values and C3G content become larger as storage temperature increased. Anthocyanin extract from black rice bran was very stable, as C3G content after storage at all temperatures was maintained at more than 90% of initial content. These results suggest that anthocyanin extract from black rice bran may be useful as a natural food colorant.