Page:Popular Science Monthly Volume 30.djvu/397

Rh made in factories by the process just described. Massachusetts, New York, and some other Eastern States have laws concerning vinegar. In these States the cider-vinegar may be depended on as being really made from cider, for the risk of heavy penalties is incurred by offering anything else under this name. The laws require, also, that all vinegar shall contain four and a half per cent of acetic acid. Cider-vinegar contains a little malic acid, and will give a precipitate with acetate of lead. The absence of the precipitate shows that the sample is not cider-vinegar; but other vinegar, to which malic acid has been added, will, of coiirse, yield the precipitate. Many persons still retain a strong preference for cider-vinegar, but this, like the old preference for feather-beds, is gradually passing away. As rotten apples, and more or less of other kinds of dirt, commonly go into the cider-mill with the sound fruit, and no thorough purification of the product is attempted, not much can be said for home-made cider-vinegar on the score of purity. Many times as much white-wine as cider vinegar is now consumed in the United States, The white-wine vinegar, however, is not made from white wine, as that beverage is not sufficiently abundant in this country to supply the demand of the vinegar-manufacture. Until recently, manufacturers started with whisky, rum, or other alcoholic liquor, but they are now allowed to produce their own spirits. In the East, molasses, and in the West a wort from grain, is first fermented in a vinegar-still—an apparatus having no worm—and a liquor containing fifteen to twenty per cent of alcohol is produced. The liquor is then converted to vinegar in the usual way. This vinegar is perfectly colorless, and the brownish color which the consumer expects in vinegar is given to it by the addition of some harmless substance, as burned sugar, or an infusion of roasted barley-malt. Cider-vinegar has an agreeable flavor, due to the presence of acetic ether and malic acid. Vinegar from well-flavored wines is the most agreeable, as the ethers which give the bouquet to the wine produce a pleasant flavor in the resulting vinegar. Whisky containing fusel-oil yields a pleasant vinegar, as the fusel-oil during the acetification is decomposed into fragrant ethers. Vinegar is flavored artificially by adding to the last wash oil of cloves, or some fragrant ether.

A recipe is given in Ure's "Dictionary," by which it is said that an excellent vinegar for domestic use can be made. To each gallon of a sirup, containing one and a quarter pound of sugar to a gallon of water, is added one quarter of a pint of good yeast. The liquid is kept at a temperature of from 75° to 80° Fahr. for two or three days, and is then racked off from the sediment into the ripening-cask, where one ounce of cream of tartar and one ounce of crushed raisins for each gallon is mixed in. When the vinegar is freed from any sweet taste, it is drawn off clear into bottles and closely corked.

Vinegar should not be kept in metallic vessels except those of silver or perfectly clean copper. Earthenware glazed with oxide of