SOLVENT EXTRACTION OF ANTHOCYANINS FROM WINE POMACE

TLDR

Natural pigments from abundant sources such as wine grape pomace are sought as food colorants. The study investigates how solvent type and acid type influence anthocyanin extraction from grape pomace. Extraction was evaluated by varying solvents (ethanol, methanol, water) and acids (HCl, citric, tartaric, formic, acetic, propionic). Methanol extracted 20 % more anthocyanins than ethanol and 73 % more than water; HCl was most effective with ethanol but corrosive, while citric acid performed best with methanol and acetic acid with water.

Abstract

ABSTRACT There is considerable interest in utilization of natural pigment as food colorants, particularly from raw materials in adequate supply, such as wine grape pomace. The rate and degree of extraction of anthocyanins from grape pomace depends upon a number of factors; this research concerned two: solvent (ethanol, methanol, water), and acid (HCl, citric, tartaric, formic, acetic, propionic). Methanol was the best extractant being 20% more effective than ethanol and 73% more effective than water. HCl was most effective with ethanol, but is also very corrosive. Of the organic acids, citric was most effective with methanol and acetic acid with water.