478 
causes it, by due attention in the vat and the cask; but once 
a wine is pricked it should, says Dr. Guyot, “be sent to the 
vinegar factory, and never attempt to use it as wine.” 
The remedies proposed are only palliatives, but are not 
radical cures. Pasteurisation will stop it, but won’t re- 
move the acetic acid in the wine. “Even after its neutrali- 
sation by means of alkaline substances the wine will still 
have an odour of acetic acid, accompanied besides by a 
bitter taste which lingers in the throat.” 
Jlilk-sour, Lactic Acid—A sickly rancid, sour-sweet taste, 
caused by lactic fermentation, which takes place in wine 
that has fermented at too high a temperature. A milk- 
sour wine loses some of its fluidity, and its colour becomes 
dull. Pasteurising will check the disease, but it is almost. 
impossible to take away the defect of milk-sourness. 
GEROPIGA. 
During vintage a stock of grape syrup is sometimes laid by for 
the purpose of sweetening any port wine lacking in fruitiness. For 
that purpose, erush dead-ripe grapes and press out the juice, evapo- 
rate on a slow fire in a copper or an iron boiler, heating to a simmer 
to prevent the formation of caramel and keeping the surface well 
skimmed. When the bulk is reduced to half its volume, add more 
grape juice, and continue simmering until syrupy, with a specific 
eravity of 25deg. B, then foctify to 32deg. proof. 
By carrying the concentration to 32deg. Baumé, the grape 
syrup will keep. This preparation is known as arropa in Spain, 
and is used in the manufacture of Malaga wine. In Italy, under 
the name of sapa, it is used for a similar purpose. 
PIQUETTE FOR DISTILLATION. 
The pressed mare or cake made up of the skins from the fer- 
menting vates still contain a notable quantity of wine which cannot 
be extracted by the press but which ean profitably be made avail- 
able for the still without impairing the value of the residue for the 
feeding of stock or as a manure. One ton or 2,240 lbs. of fresh 
grapes will yield about 1,300 lbs. of wine and 700lbs. of mare or 
skins and pips. From this mare another 20 to 30 gallons of wine 
can be utilised for the spirit it contains. Two methods are employed 
for that purpose :—l. Driving the alcohol direct from the mare by 
means of steam and condensing the spirit. 2. Washing out by a 
process of lixiviation or of diffusion. 
The first method is, of course, carried out in closed retorts. 
The second consists of a battery of four or five vats, either 
wooden or made of reinforced concrete and built on the same level 
They communicate with one another by means of pipes. The vats 
