Protein Removal from a Wine by Immobilized Grape Proanthocyanidins

Abstract

Proanthocyanidins from grapes were isolated and immobilized on agarose. The immobilized proanthocyanidins bound proteins from an unfined Gewürztraminer wine, resulting in a protein-stable wine as judged by a TCA turbidity test. Several regenerating solvents for the proanthocyanidins-agarose column were investigated, with alkaline solutions being most effective. As a means of achieving protein stability in wine, the use of immobilized proanthocyanidins is apparently limited by reduction in protein-binding capacity after a small number of regeneration cycles.