Implements for stirring.
Method of Operation.—After preparing the finings as described under the head of each of the substances already mentioned, two or three gallons of wine are drawn from the bung by the aid of a siphon, pump, or other suitable implement, the finings are poured in, and the wine is stirred until thoroughly mixed with them. This may be done with a stick split at the end into three or four prongs ([fig. 24]), or by a sort of brush consisting of several small bundles of bristles inserted in a stick and at right angles to each other ([fig. 25]), or with a sort of bent paddle, pierced with holes, called a whip ([fig. 26]). The wine drawn out should then be replaced in the cask, which should be completely filled, and left to rest till the wine is bright. In filling a cask which has recently been agitated, or into which finings have been put, a good deal of froth is frequently found which will run out at the bung before the cask is full, and will prevent the operator from filling it. A few smart blows on the bung stave with a bung starter will break the bubbles and remove the foam. The time required to clarify a cask of wine depends somewhat upon the quality of the wine itself, and also upon the kind of finings used. The usual time is from two weeks to a month. In no case, however, should it be allowed to remain on the finings after it has cleared and has ceased to deposit, for the sediment may work up again and cloud the wine, and if left too long in contact with the deposit, the wine may acquire a disagreeable flavor.
If, after leaving the wine a suitable time, it still remains turbid and continues to deposit, it should be racked into a clean cask and fined again, adding tannin, if necessary.
CHAPTER XIV.
SWEET WINES—FORTIFIED WINES.
Generally.—The French give the name vins de liqueur, liqueur wines, to sweet wines, and it is also sometimes applied to fortified dry wines. Sweet wines are those which, after terminating their active fermentation, still retain a quantity of sugar. In order to produce natural sweet wines, it is necessary that the must should contain a large amount of sugar; Boireau says, from 16° to 25° Baumé, or about 29 to 46 per cent. It would seem that the latter figure is too high for a natural sweet wine, for it probably would not ferment at all, and to make a wine from a must containing over 35 per cent. of sugar, the alcohol must be added. (See [Musts].) He goes on to say that these wines will contain from 15 to 16 per cent. of natural alcohol, without addition; the sugar which they contain makes them heavier than water.
To Increase Sugar.—In order to augment the amount of sugar, the grapes are left on the vine till they become excessively ripe; in some places the stem of the bunch is twisted on the vine to interrupt the rising of the sap; the must is also sometimes concentrated by boiling; sometimes the grapes are picked and exposed to the sun on screens or straw mats, until they become shriveled, and sometimes they are dried in ovens.
Without Fermentation.—Sometimes sweet wines are made without allowing the must to ferment at all, by adding alcohol till it contains 18 or 20 per cent. of spirit; thus all the sugar is preserved. Again, they are made by mixing with dry wines grape syrup or concentrated must, and fortifying.
Care Required.—It has already been stated in the chapter on keeping wine that these wines require less care than weaker ones. But Mr. Boireau says that wines, whether sweet or dry, whose strength does not exceed 16 per cent., require the same care as ordinary wines.
In order that sweet and fortified wines may be kept in storehouses subject to great changes of temperature, in bottles upright, or in casks in ullage—in other words, under the conditions in which brandy can be kept, they must contain 18 or 20 per cent. of alcohol. They age sooner in casks than in bottles. (See [Aging].)