AN ENZYME-ENHANCED EXTRACTION of ANTHOCYANINS from RED CABBAGE and THEIR THERMAL DEGRADATION KINETICS

Abstract

There is a great demand for developing efficient anthocyanins extraction related to each plant material. Conventional methods haw been replaced by novel techniques, but they might remain attractive when combined with the latter. Anthocyanins extraction from fresh and dried red cabbage was investigated by maceration, ultrasomcation, and with enzymes. Pre-treatments through drying determined an improved extraction with respect to fresh samples, freeze-drying emerging as the best method. Combined enzyme-assisted extraction with maceration resulted in higher yield by conducting several extractions (1078.8±12.5 mg'100 g DUO-The kinetic studies revealed good stability of anthocyanins at 50 °C, while constant degradation at 80 °C. The rate constant k at 80 °C and pH 3.5 was 1.7 10"3 mm-1 and the half-life time r^was 6.7 h. Thermal analysis evidenced heat-induced changes in particular for extracts undergoing pre-heating. These results are valuable for optimal processing conditions of anthocyanins-contairung products.