Kinetics of Anthocyanin Extraction from Fresh and Dried Grape Waste

Abstract

Anthocyanins are natural pigments which can be extracted from grape waste. Anthocyanin extraction from fresh and dry grape waste was studied using various solvents. Six solvents were employed, and methanol with 0.1% (v/v) HCl provided the highest extraction of 1.18 x 10(-3) g.g(-1) for dry waste. The same solvent also exhibited the fastest kinetics and the shortest time (7 hours) required to attain equilibrium. The kinetics of extraction were well-described by a two-interface mass transfer model which considered the solvent diffusion effects on the mass transfer coefficients. equilibrium and hold-up studies were also carried out using the safest solvent for human consumption from among the solvents used for extraction