Study on the Ultrasonic-Assisted Extraction Process of Anthocyanin from Purple Cabbage with Deep Eutectic Solvent

In this paper, purple cabbage was used as raw material for ultrasonic-assisted extraction of anthocyanin with deep eutectic solvent. The effects of extraction solvent type, solid-liquid ratio, moisture, extraction temperature, and time on the yield of anthocyanin from purple cabbage were investigated by single factor test, and the feasibility of this extraction method was verified by standard addition recovery test. The test results showed that the optimal extraction results could be obtained when DES-5 (choline chloride/1, 2-propylene glycol/water) is used as extraction solvent, with solid-liquid ratio of 1:32, moisture of 50%, extraction temperature of 50 °C, and extraction time of 80 min. Under these conditions, the yield of anthocyanin extract purple cabbage reached 21.6%, and the recovery rates were 85.62-87.75%. Therefore, DES was a promising environmentally friendly solvent for extracting anthocyanins instead of organic solvent extraction.