VINEGAR, PICKLES, AND PICKLING All vinegar, of which there are several kinds, consists of et dilute so lution of acetic acid in water with a small amount of sugar and other organic matter. Vinegar is the result of the action of the oxygen of the air, in the presence of a particular kind of yeast or ferment, upon CL so lution of alcohol. The alcoholic liq uors from which vinegar is made may be produced by the fermenta tion of almost any vegetable or fruit juices. The principal kinds of vine gar are, accordingly, wine vinegar, produced from grapes; malt vinegar, from barley; cider vinegar, from apples; sugar and molasses vinegar, from cane sugar products; corn vine gar; beet vinegar; etc. The alcoholic fluid, or " wash," as it is called, should contain not over 4 per cent to 12 per cent of alcohol. And for the best re sults the temperature should be from 70 per cent to 85 per cent Fahrenheit. Plenty of air to introduce the oxygen required by the process must be sup plied and mixed with the alcoholic solution. The changing of alcohol to acetic acid by the action of oxygen produces heat and increases the weight of the liquid.
Commercial vinegar is made on the Continent of Europe principally from cheap grades of wine, in England from malt and sour beer, in the United States from cider and cheap grades of alcoholic liquors, as whisky and the like.
Methods of Making Vinegar. — There are two principal ways of making vinegar —the slow and the quick process. In the former the al coholic solution is placed in a barrel or vat containing a little old vinegar or mother, which supplies the neces sary yeast, or in the case of wine vinegar, old wine lees, either exposed to the sun or placed in a warm room. Air is admitted through the bung of the casks or otherwise, and the liquid is allowed to stand until it turns to vinegar. This takes two weeks or more in summer, and a month or more in cold weather. The process is similar to that of making cheap vine gar from molasses and yeast, or mak ing ordinary cider vinegar.
Or to make vinegar by the quick, or German process, prepare a special contrivance as follows: Supply a large vinegar cask with a false bottom about a foot from the true bottom perforated with a large number of I inch gimlet holes. If a fine quality of vinegar is desired, cover this with one or more thick nesses of white flannel cloth, and an inch layer of clean white sand on top. Bore, around the outside of the bar rel an inch below the false bottom, a row of inch auger holes slanting downward from without 2 or 3 inches apart. These are necessary to admit the air. Fill the barrel from the false bottom to within 4 or 5 inches of the top with maple, beech, or basswood chips previously soaked for three or four days in first-class vinegar.
Now cut another cask of somewhat smaller size in halves. Bore the bot tom of one half barrel full of gimlet holes the size of a goose quill or about /t inch in diameter. Cover this with cotton batting or yarn, and place it on top of the barrel resting on cross slats or upon the chips.
Insert a spigot into the cask below the false bottom, slanting downward to the bottom of the cask but having its opening just below the level of the row of air holes, and place be neath the spigot the other half barrel, protected by a wooden cover from dust and dirt.
The alcoholic liquor poured into the upper half barrel causes the yarn or cotton in the bottom to swell and fill the gimlet holes, whence the liquor drops through upon the chips. The process of fermentation produces heat, which causes a current of air to rise through the openings for that purpose below the false bottom, and to meet the alcoholic liquor as it per colates drop by drop through the chips. The air current escapes be tween the bottom of the upper half barrel and the top edges of the large cask. Thus the action of the oxygen in the air in turning the alcohol into acetic acid is made very rapid.