The highest yield of anthocyanin was obtained at 60 C with water-ethanol (1:1) in 10% citric acid; whereas, maximum yield of the same under SC-CO2 conditions were obtained with 10 g of citric acid pre-treated peels at 60 C, 10 MPa with 1.5 h extraction time at a flow rate of 0.2 L min1 of CO2.
Delphinidin-3-glucoside and delphinidin-3-rutinoside were tentatively identified as the major anthocyanins in the extracted colors.
These methods of extraction of eggplant peel color are reported for the first time.
The solventextracted color, more stable at high temperature regimes was suitable for thermal food applications while the SC-CO2 extracted color is recommended for non-thermal food applications owing to its higher stability and lower metal contamination.