FINING, the process of clearing turbid liquors, such as beer, wine, etc. The sim plest mode of F. is by passing the liquor through a porous substance that retains the solids and allows the clear liquid to pass through (see FILTER); but this method is only applicable to particles mechanically suspended in a limpid liquid. When the liquid contains mucilaginous or other matter, that readily clogs the filter, some other means of F. must be used. Such is the case with all malt liquors and most wines when turbid. When in good condition, these do not usually require F., as the suspended matter agglomerates, and sinks to the bottom shortly after the fermentation is completed. When this does not take place, some means of promoting such action are usually adopted. One of the simplest is to add soluble albumen, such as white of egg, to a portion of the liquid, and after beating it well in this, to add the mixture, and stir it into the whole of the liquid. Upon the application of heat, the albumen coagulates and contracts from its diffusion into a scum, enveloping and drawing together the suspended matter. The scum is then easily removed. This method is adopted for sirups and other liquids that may be heated without mischief. In making clear soups, the albu men of the meat performs this function. As alcohol coagulates albumen, it maybe used for fining wines and cordials without the application of heat. It is generally used for red wines. Malt liquors are usually fined by means of gelatine, either isinglass or cheaper substitutes used. One pound of isinglass is soaked in three or four pints of water, or sour beer, then more sour liquor added as the isinglass swells, until it amounts to about a gallon. The jelly thus formed is next dissolved in seven or eight gallons of the liquor to be fined. This solution, having the consistence of a sirup, is called "brewers' finings," and about a pint to a pint and a half is added to a barrel of ale or porter, or to a hogshead of cider or wine. The action of this depends upon the
combination of the gelatine with the astringent matter (tannic acid) of the liquor, form. ing thereby an insoluble solid, which sinks to the bottom, and carries with it, like the coagulating albumen, the suspended matter; but as the flavor of malt liquors partly depends upon the astringents they contain, the- F. affects the flavor; the astringents also help to preserve the liquor, and hence their removal is in this respect disadvanta geous. Malt liquors thus fined do not "stand well on draught." The use of gelatine for F. red wines is objectional, as in most of these the astringent flavor is an esteemed quality, and therefore albumen is preferred.
Other methods of F. are adopted. Sugar of lead is sometimes added, and after wards, one half its wOgict alsSolved in water. By this means, an insoluble sulphate of lead is precipitated; which in subsiding carries down other mat ters with it. This is a dangerous process, the salts of lead being poisonous. If prop. i erly conducted, the whole of the lead may be precipitated, but a casual mistake in the quantities might cause the death of many people. Ox-blood is used in the same man ner as albumen and isinglass. Lime, alum, alcohol, and acids act by coagulating albumen, etc., contained in the liquor. Plaster of Paris, clay, and even sand, are some times used to carry down the suspended matters. A strip of isinglass or a piece of dried sole-skin is often used for F. coffee, and it acts iu the manner above described. Liquors that are unusually difficult to rine are called "stubborn " by coopers and cellarmen.