PT  - JOURNAL ARTICLE
AU  - Richard G. Peterson
AU  - Arthur Caputi, Jr.
TI  - The Browning Problem in Wines II. Ion Exchange Effects
AID  - 10.5344/ajev.1967.18.3.105
DP  - 1967 Jan 01
TA  - American Journal of Enology and Viticulture
PG  - 105--112
VI  - 18
IP  - 3
4099  - http://www.ajevonline.org/content/18/3/105.short
4100  - http://www.ajevonline.org/content/18/3/105.full
SO  - Am J Enol Vitic.1967 Jan 01; 18
AB  - The effects of Na+ exchange, H+ exchange, and H+ exchange followed by OH- exchange on browning of four dry white wines were compared in the presence and in the absence of oxygen,Wines browned more when oxygenated than when stripped with N2, and ion-exchanged wines browned less than the untreated controls. H+ exchange was more effective than Na+ exchange in inhibiting the browning of all wines. H+ exchange, followed by OH- exchange practically eliminated browning, but wines so treated were water-white and retained little wine character. This pattern was similar for samples stored at ambient temperatures for 18 months as at 110°F for 24 days.Varietal effect remains an important factor in determining the extent of browning to be expected in white wine. Evidence is presented which indicates that two distinct types of browning may occur simultaneously in wine, oxidative and non-oxidative, and that the varieties differ in their capacities for each. This work indicates that Palomino wine browning is essentially oxidative, but that French Colombard wine is capable of considerable browning both in the absence of oxygen and in its presence. Even at 140°F the Palomino browned little without 02, but drastically when O2 was introduced.Added brown wine did not affect browning rate or extent in any of the wines tested, and it is concluded that there is no autocatalytic effect.