Organic acids

Abstract

Because they play a pivotal role in maintaining the quality and nutritional value of a variety of foods, organic acids are among the most frequently assayed substances in this type of substrate. The organic acids present in foods originate from biochemical processes;from their addition as acidulants, stabilizers, or preservatives; or from the activity of some microor-ganisms (particularly yeasts and bacteria). They con-tribute tothe sensory properties of foods. In fact, the role of organic acids in the taste and aroma of alcoholic beverages is well documented (1); the sour, sharp, and irritating flavors of cider are ascribed to lactic acid, totalacidity, and acetic acid, respectively.Malic and acetic acids bear a negative though signifi-cant correlation to sweet taste and scented flavors;also, they taste equiacidic with solutions containing sucrose (e.g., 0.7%D-tartaric acid with a 0.8% concentration of this acid plus 2% sucrose) (2).Acetic acid and the global hedonicscore for fermented beverages also bear a significant negative mutual correlation. Organic acids may exhibit other sensory properties.For example, citric acid possesses sour-and-sweet sensory notes, and succinic acid has asalty-bitter taste. On the other hand, the typical taste and flavor of Emmental cheese can be ascribed to propionic acid and