VINEGAR. Under the head Ammo ACID is given the mode of making vine gar from alcohol. Under the present head will be noticed the manufacture from fermenting vegetable juices. Al most all the vinegar of this country is made from cider. It is only lately, how ever, that any regularity or care in the manufacture was exhibited.
The old mode was to put out cider or water and molasses in a cask, exposed to the sun, until it became fully fermented. (See FERMENTATION.) The oxygen of the atmosphere, al though it is not now, as was once believ ed to be, the only acidifier, still it is the great one, and vinegar is formed by the cider parting with carbonic acid gas, which it cannot do without absorbing oxygen. The reasonable way, then, to make vinegar rapidly and surely is to expose the cider as much as possible to the atmosphere. The new way, and what is supposed by many, incorrectly, to be a patent way to make vinegar, is to let the cider percolate over a very exposed sur face. The apartment where it is made is freely exposed to the air, and is kept at a temperature of above 60°. The cider is left to run in small streams into troughs with bottoms full of small holes, then from that over very fine wood shavings, such as soft maple, and let those be ful ly exposed to the air and resting on a slatted bottom made of clean bows or laths, below which the vessel for receiv ing it should be placed ; vinegar can be made from molasses and water, grapes, corn stalks, beet roots, and many other substances, by this process in a few days. Cider, however, makes the best vinegar. Many modifications (for cheapness) of the above plan may be resorted to, the grand secret being the exposure of the liquids to be changed into vinegar in layers or strata to the oxygen of the at mosphere.
The following is the plan cf making vinegar at present practised in Paris. The wine destined for vinegar is mixed in a large tun with a quantity of wine lees, and the whole being put into sacks, placed between the plates of a press, the liquid matter is pressed out.
What passes through is put into large casks, set upright, having a email aper ture in their top. In these it is exposed to the heat of the sun in summer, or to the heat of a stove in winter.
Fermentation comes on in a few days. If the heat should then rise too high, it is lowered by cool air, and the addition of fresh wine. In summer the process is generally completed in a fortnight • in winter double the time is requisite. The vinegar is then run of into barrels, which contain several chips of beech wood to clarify it : in about a fortnight it is fit for sale.
Almost all the vinegar of the north of France being prepared at Orleans, the manufactory of that place has acquired such celebrity as to render their process worthy of a separate consideration.
The Orleans casks formerly contained nearly 200 gallons of wine, but at present only about half that quantity. Those which have been already used are pre ferred. They are placed in three rows one over another, and in the top have an opening of two inches diameter, which has a bung fitting close ; there is another spill hole on the side to admit the air. Wine a year old is preferred for making vinegar, and is kept in adjoining casks, containing beech Shavings, to which the lees adhere.
The vinegar from sugar is made as fol lows :—Ten pounds of sugar are added to eight gallons of water, with yeast and raisins or grape cuttings, to assist in the fermentation ; twelve pints of bruised gooseberries, or other fruits, are added ; and, by a process similar to that for cider, good vinegar is soon produced.
By distillation the coloring matter in mucilage is separated ; but the fragrant odor is generally replaced by an empy reumatic one.
The specific gravity varies from 1.005 to 1.015.
The Vinegar of Wood, as it comes over in the first distillation, with its tar and ompyreumatic oils, is extensively used in preserving meat and all animal substan ces. A single dipping, or washing, de stroys all tendency to putrescence and decomposition, and operates like its smoke, in curing hams, fish, &c. This pro is I perty s due to the presence of creosote.
It is also found to be highly efficacious in checking putrescence in wounds and ulcers, and in arresting scrofula, and obstinate local inflammations.
It is prepared by the destructive distil lation of any kind of wood. It is then re-distilled in a copper still, leaving one fifth residuum of tough, tarry matter. The product, brown vinegar, is then dis tilled a third time, and absorbed by lime, dried, and torrified as calcareous salt. This is decomposed by sulphuric acid, and the product is pure acetic acid. At 75°, one part with 11 of water is the com mon distilled vinegar of medicine.
Pyroligneous acid is prepared, quite colorless, by distillation from the acetate of lime above mentioned, is of sp. gr. 1.003, and is seven times stronger than table, or pickling vinegar, and requires seven volumes of water for culinary pur poses. A piece of meat, or a whole ani mal dipped in it, or sponged, or brushed with it, remains sweet and free from putrescence for months or years.
Ibur-thieves Vinegar.—In two pints of strong acetio acid, for 7 days, digest 1 oz. of rosemary-tips and of sage-leaves, an oz. of lavender-naps, and 1 scruple of cloves ; (some add half a clove of garlic.) Press well, and filter.