pro·pi·on·ic acid (prō′pē-ŏnĭk)
An oily liquid acid, C3H6O2, found naturally in sweat, in milk products, and as a product of bacterial fermentation. Prepared synthetically from ethyl alcohol and carbon monoxide, it is used chiefly in the form of its propionates as a mold inhibitor in bread and as an ingredient in perfume. Also called propanoic acid.
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