bitter; bitterness
bitterness in wine can be due to tannins, chemical salts, oxidized polyphenols, bacteria, and even some grapes (such as Gewürztraminer), which have an intrinsically bitter note. Slight bitterness can contribute balance to a sweet wine. Overt bitterness that dominates a wine’s flavor or aftertaste is considered a fault.
The New Wine Lovers Companion, 2nd Edition, by Ron Herbst and Sharon Tyler Herbst. Copyright © (1) 2003, 1995 by Ron Herbst and Sharon Tyler Herbst. Reprinted by arrangement with Barron's Educational Series, Inc.