Term for the state in which fats and other lipids (oils, waxes) decompose by oxidation or by fat-splitting enzymes. The reaction products are often smelly or bad-tasting substances (including free fatty acids) that make food inedible. Rancid notes can also occur in wine; in Spanish rancio (Spanish for rancid) or oxidatively matured wines, this is even deliberately encouraged, because in a small degree such notes give a thoroughly positive impression. Related terms of rancid are firnig, madeirisiert, oxidiert and rahn.
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