Question No.  15120 :
Who discovered ethanoic acid (vinegar), and when?

Vinegar making is one of the most ancient of natural fermentations. Vinegar was undoubtedly first made by allowing fermented liquids to acetify naturally but wine was probably the first raw material used in its commercial manufacture. The word vinegar comes from two French words vin and aigre ('sour wine"), but the term vinegar applies to any product made by the acetous fermentations of a wide variety of materials. Actually, the manufacture of vinegar is a two-stage process -- (a) the conversion of sugar to alcohol by yeast; and (b) the conversion of alcohol to acetic acid by bacteria. Thus vinegar can be produced from any liquid capable of first being converted to alcohol. Nowadays, vinegar is produced by the action of yeast and bacteria on agricultural products, including fruit, grain, and such sugar solutions as honey and molasses. Vinegar sold for use at home typically contains 5 per cent acetic acid (or ethanoic acid). But it may contain as little as 4 per cent. Most vinegar used in commercial food processing contains from 12 to 15 per cent acetic acid. People used vinegar and wine as antiseptics as early as 2,500 years ago, long before the discovery that germs cause disease. Several hundred years ago, surgeons noticed that untreated battle wounds and surgical incisions quickly began to smell like rotting flesh. To prevent this odour, they treated the tissues with a variety of substances that became known as antiseptics. The word comes from two Greek words--anti, meaning against, and sepsis, meaning decay. Georg Stahl, a German chemist, first isolated glacial acetic acid from vinegar in 1700. Commercially, the acid is usually produced by such chemical processes as the oxidation of acetaldehyde with air in the presence of catalysts. Acetic acid is an important organic acid and industrial chemical. One of the chief uses of acetic acid is as an intermediate for making other chemicals. Manufacturers convert it into acetic anhydride and acetate esters. Acetic anhydride is used to make acetate fibres and cellulose acetate, a plastic. Ethyl acetate is an important ester used as a solvent for varnishes and in nail polish remover. As a reagent, acetic acid is used to make synthetics, rubber, and aspirin and other pharmaceuticals. It is also widely used as an acid and solvent. Question Asked By:

Name: Di

Age Group: 13 to 20

Occupation Type: Student

Education Level: Others