Effects of Solid-Liquid Ratio, Time, and Temperature on Water Extraction of Anthocyanin from Campbell Early Grape

Abstract

This study was conducted to optimize anthocyanin extraction conditions from Campbell Early grape using acidified water. A response surface methodology with Box-Behnken design consisting of 17 experiments was employed to investigate the effects of three variables. The grape was extracted at three different solid-liquid ratios (1/30-1/50 g/mL), extraction times (10-60 min), and extraction temperature (30-80 degrees C). Under optimum conditions (1/50 g/mL, 10 min, and 80 degrees C), experimental values were 197.52 mg/100 g for total anthocyanins, 1363.12 mg/100 g for total phenols, and 315.79 mg/100 g for 2,2 '-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity in the dry weight basis. The difference between experimental and predicted values was less than 5.1%, indicating that the model fits well. Eight anthocyanins were identified in the extract of Campbell Early grape using an ultra-performance liquid chromatograph (UPLC) with a tandem mass spectrometry. Three major anthocyanins were cyanidin-3-(coumaroyl)-5-diglucoside (44.1% of the total), delphinidin-3-(coumaroyl)-5-diglucoside (20.7% of the total), and peonidin-3-(coumaroyl)-5-diglucoside (12.4% of the total).