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CHAPTER IX
ORGANIC ACIDS, ACID SALTS, AND ESTERS
Organic acids, either in free form, or partially neutralized with calcium, potassium, or sodium, forming acid salts, or combined with various alcohols in the form of esters, are widely distributed in plants. They occur in largest proportions in the fleshy tissues of fruits and vegetables, where they are largely responsible for the flavors which make these products attractive as food for men and animals. But organic acids and their salts are also found in the sap of all plants, and undoubtedly play an important and definite part in the vital processes of metabolism and growth.
CHEMICAL CONSTITUTION
All organic acids contain one (or more) of the characteristic acid group, —COOH, or
