Effects of Microwave Power on Extraction Kinetic of Anthocyanin from Blueberry Powder considering Absorption of Microwave Energy

Abstract

Microwave power as directly controlled parameter determines the absorption of microwave energy inside extraction vial and the yield of objective component in microwave-assisted extraction (MAE). The aim of this study was to elucidate the effects of microwave powers on the yield of anthocyanin from blueberry (Vaccinium spp.) powder based on the absorption of microwave energy in extracts under MAE. Rising microwave powers have little effect on the distribution of microwave energy in extraction vial, but increase its temperature. The simulation results indicated that strength of electrical field tends to decay trend along with microwave irradiation; however, temperatures have the highest level in center location in an extraction vial. High microwave power strongly breaks cell wall of blueberry to open diffusion route of interior anthocyanin toward extraction solvent. A critical extraction temperature of 50.75±0.88°C is obtained with the highest anthocyanin yield under MAE. Three monomers of anthocyanin including pelargonidin, cyanidin, and delphinidin are, respectively, of the highest content of 1.02 μg/mL, 0.66 μg/mL, and 0.31 μg/mL. The research results contribute to the improvement of efficiency of microwave energy and yield of anthocyanin.