Unpleasant bitter. earthy and rancid odor and taste after grated leaves and flowers of geranium (popularly pelargonium), by reaction of the preservative sorbic acid With bacteria like acetic acid or Lactic acid bacteria arises. The wine faults For example, at the malolactic fermentation (BSA) occur, where indeed lactic acid bacteria are active. The problem first appeared in the second half of the twentieth century, when it became more common grape or wine to add sorbic acid.
This is due to bacterial attack by reaction with ethanol (Alcohol) converted to 2-ethoxy-3,5-hexadiene. Even very small amounts of the very intense tasting substance in ten-billion-fold dilution are clearly perceptible as Geranienton. Troubleshooting is nearly impossible, not even by activated carbon, The error can only be prevented by large cellar hygiene, possible sources of distribution are contaminated containers (fermentation vats, barrels, bottles), hoses and filling equipment. See also below wine faults,