A dictionary of chemistry, on the basis of Mr. Nicholson's: in which the principles of the science are investigated anew, and its applications to the phenomena of nature, medicine, mineralogy, agriculture, and manufactures, detailed (Volume 1).
- Andrew Ure
- Date:
- 1821
Licence: Public Domain Mark
Credit: A dictionary of chemistry, on the basis of Mr. Nicholson's: in which the principles of the science are investigated anew, and its applications to the phenomena of nature, medicine, mineralogy, agriculture, and manufactures, detailed (Volume 1). Source: Wellcome Collection.
Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)
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![which they pour such wine as they wish to acetify; and it is always preserved full, hv replacing' the vinegar drawn off, by new ■wine. To establish this household manu- facture, it is only necessary to buy at first a small cask of good vinegar. At Gand a vinegar from beer is made, in which the following proportions of grain are found to be most advantageous :— 18S0 Paris lbs. malted barley. 700 wheat. 500 buckwheat. These grains are ground, mixed, and boil- ed, along with twenty-seven casks-full of river water, for three hours. Eighteen casks of good beer for vinegar are obtain- ed. By a subsequent decoction, more fer- mentable liquid is extracted, which is mix- ed with the former. The whole brewing yields 3000 English quarts. In this country, vinegar is usually made from malt. By mashing with hot water, 100 gallons of wort are extracted in less than two hours from 1 boll of malt. When the liquor has fallen to the temperature of 75° Fahr. 4 gallons of the barm of beer are added. After thirty-six hours it is racked off into casks, which are laid on their sides, and exposed, with their bung-holes loose- ly covered, to the influence of the sun in summer; but in winter they are arranged in a stove-room. In three months this vinegar is ready for the manufacture of su- gar of lead. To make vinegar for domes- tic use, however, the process is somewhat different. The above liquor is racked off into casks placed upright, having a false cover pierced with holes fixed at about a foot from their bottom. On this a consid- erable quantity of rape, or the refuse from the makers of British wine, or otherwise a quantity of low priced raisins, is laid. The liquor is turned into another barrel every twenty-four hours, in which time it has begun to grow warm. Sometimes, indeed, the vinegar is fully fermented, as above, without the rape, which is added towards the end, to communicate flavour. Two large casks are in this case worked togeth- er, as is described long ago by Boerhaave, as follows. Take two large wooden vats, or hogs- heads, and in each of these place a wooden grate or hurdle, at the distance of a foot from the bottom. Set the vessel upright, and on the grate place a moderately close layer of green twigs, or fresh cuttings of the vine. Then fill up the vessel with the footstalks of grapes, commonly called the rape, to the top of the vessel, which must be left quite open. Having thus prepared the two vessels, r>our into them the wine to be converted into vinegar, so as to fill one of them quite up, and the other but half full. Leave them thus for twentv-four hours, and then Vor.. i. [2] fill up the half filled vessel with liquor from that which is quite full, and which will now in its turn only be left half full. Four-and-twenty hours afterwards repeat the same operation, and thus go on, keep- ing the vessels alternately full and half full during twenty-four hours, till the vinegar he made. On the second or third day there will arise in the halffilled vessel, a fermen- tative motion, accompanied with a sensible heat, which will gradually increase from day to day. On the contrary, thejerment- ing motion is almost imperceptible in the full vessel; and as the two vessels are al- ternately full and half full, the fermenta- tion is by this means in some measure in- terrupted, and is only renewed every other day in each vessel. When this motion appears to have en- tirely ceased, even in the halffilled vessel, it is a sign that the fermentation is finished; and therefore the vinegar is then to be put into casks close stopped, and kept in a cool place. A greater or less degree of warmth accelerates or checks this, as well as the spirituous fermentation. In France it is finished in about fifteen days, during the summer; but if the heat of the air be very great, and exceed the twenty-fifth degree of Reaumur's thermometer, (88±° Fahr.) the halffilled vessel must be filled up eve- ry twelve hours ; because, if the fermen- tation be not so checked in that time, it will become violent, and the liquor will be so heated, that many of the spirituousparts, on which the strength of the vinegar de- pends, will be dissipated, so that nothing will remain after the fermentation but a vapid liquor, sour indeed, but effete. The better to prevent the dissipation of the spirituous parts, it is a proper and usual precaution to close the mouth of the half filled vessel, in which the liquor ferments, with a cover made of oak wood. As to the full vessel, it is always left open, that the air may act freely on the liquor it con- tains ; for it is not liable to the same in- conveniences, because it ferments but very slowly. Good vinegar may be made from a weak sirup, consisting of 18 oz. of sugar to eve- ry gallon of water. The yeast and rape are to be here used, as above described. Whenever the vinegar (from the taste and flavour) is considered to be complete, it ought to be decanted into tight barrels or bottles, and well secured from access of air. A momentary ebullition before it is bottled is found favourable to its preserva- tion. In a large manufactory of malt vine- gar, a considerable revenue is derived from the sale of yeast to the bakers. Vinegar obtained by the preceding methods has more or less of a brown colour, and a pe- culiar but rather grateful smell. By dis-](https://iiif.wellcomecollection.org/image/b21160909_0033.jp2/full/800%2C/0/default.jpg)
