429 



To effect this, several methods are used. One of the most 

 common is to allow the grapes to hang on the vines until they are 

 dead ripe. The higher the state of maturity of grapes, the richer 

 they are in sugar, whilst the acidity is neutralised by the migration 

 of alkaline sap from the wood and leaves into the fruit. Also, 

 ethers are formed, which impart to the various sorts of grapes an 

 aroma peculiar to themselves. This explains why sweet wines 

 made from grapes which have been allowed to become dead ripe 

 have more individual character than sweet wines made from the 

 same grapes at an earlier period of maturity. In some localities, viz., 

 Tokay and Sauterne, which produce the most delicate sweet wines, 

 the berries are allowed to even partially rot. A fungus known as 

 Botrytis cinerea develops on the skin of the berries, and so modifies 

 the juice as to give it a very delicate flavour. 



Whether white or red sweet wine is made, it is allowed to 

 ferment for 24 hours in a large vat, and is then run out into well 

 sulphured smaller casks, and the skins are pressed. As much 

 sugar is still left in these, they are either put into another red wine 

 vat to ferment, or a little water is added, and the resulting 

 fermented mash is distilled. In the smaller casks, if necessary, a 

 sufficient quantity of well rectified spirit of wine is added, to raise 

 the alcoholic strength of the wine to 15 or 16 per cent, of absolute 

 alcohol by weight, which is equivalent to 18 to 20 by volume, or to 

 32 to 34 proof spirit. It is better not to add this spirit all at 

 once, but to bring the wine up to its full strength when the 

 saccharometer marks, according to the lesser or greater degree of 

 sweetness it is desired to give to the wine, 2 to 4 Baume, which 

 would leave in the wine 3J to 7 per cent, of unfermented sugar. 



REARING OF YOUNG WINES. 



When the freshly fermented wine is drawn from the vat into 

 the casks, a crackling sound, which is caused by a slow fermenta- 

 tion, keeps on for some little time, and as carbonic acid gas is being 

 given off all the while, the casks should not be plugged tightly, lest 

 they should burst. A good plan is to place over the bung-hole a 

 small flat sand-bag, a few inches square, which, while not interfer- 

 ing with the escaping of the gas, keeps dust, germs and the trouble- 

 some minute fermentation flies dropping into the cask. 



To the same effect, specially constructed bungs are sometimes 

 used. 



The carbonic acid gas under tension from inside the cask forces 

 its way out through the perforated plug which fits tightly into the 

 bung-hole, and, overcoming the pressure of small layers of water, 

 into which an inverted glass bell stands, escapes outside, whereas 

 the external air and all the impurities it carries in suspension, 

 cannot get access to the wine in the cask. 



Such plugs, although useful, are not indispensable to the safe 

 keeping of well fermented young wines. 



