Removal of iron, copper and manganese from white wines through ion exchange techniques:: effects on their organoleptic characteristics and susceptibility to browning

Ion exchange techniques have been used to reduce the content of iron, copper and manganese in white wines. Two exchanger resins have been compared, a chelating resin, the active group of which is iminodiacetate and a Dowex, acidic cation exchange resin. The results obtained show that the technique of using exchanger resins is extremely effective in lowering the metal content of wines, although on occasions, their use alters the organoleptic characteristics of the wine. Treated wines present lower polyphenolic and aromatic profiles than the untreated wines. Polyphenolic and metallic reductions would explain why treated wines present a notably reduced susceptibility to browning. (C) 2002 Elsevier Science B.V. All rights reserved.