CONCORD GRAPE JUICE. 13 
mentation. The cleaning of glass carboys can be more easily super- 
vised, and the siphon can be placed to better advantage in them than 
in jugs; the majority of factories therefore prefer the carboys. In 
selecting the carboys or jugs care should be taken that the mouth 
of the container has no defect and is as round as possible, so that the 
cork may fit tightly. Furthermore, in selecting glass carboys, 
vessels with perpendicular sides should be chosen in preference to 
those with sloping sides, because the former permit better settling 
of the lees or argols. To guard against possible fermentation through 
defects in the mouth of the vessels, it is a good plan to pour a small 
quantity of molten paraffin over the cork after it is in place, and 
allow the paraffin to solidify before transferring the containers to 
the vaults. The sealed vessels containing the sterile juice are 
placed in the vaults and allowed to remain undisturbed for several 
months, so that the juice may clarify and the excess of acid tartrates 
be thrown out. To obtain the best precipitation, the temperatures 
in the vaults should be kept as low as possible, i. e., as close to 32° F. 
as can be maintained without danger of freezing. 
SIPHONING THE JUICE. 
As cream of tartar is least soluble at low temperatures, the juice 
should be siphoned only during the winter months. At the close 
of the precipitation period, comprising from 4 to 5 months, the corks 
are drawn, and the clear juice siphoned into jugs. The siphon con- 
sists of an aluminum tube bent U shape, over one end of which a 
piece of rubber tubing of the desired length is drawn. The siphon 
is placed in the vessel just out of reach of the sediment, and gentle 
suction applied at the rubber end until the juice starts to flow. The 
sediment remaining in the precipitation vessels is poured on several 
thicknesses of burlap stretched on a frame, and the juice allowed to 
drain. Tins juice, which is thick and muddy on account of small 
crystals of cream of tartar and other material, is again treated in the 
sterilizer, and poured into carboys in the same manner as the juice 
proper, and again stored for precipitation and subsequent siphoning. 
This juice, called " seconds/' is mixed with the first siphoned juice. 
The residue on the burlap, called " argols," consists chiefly of acid 
salts of tartaric acid. 
Experiments conducted by manufacturers for the purpose of 
clarifying the juice during the precipitation period with the white 
of egg and gelatin have met with little or no success. This failure 
is to be expected, in consideration of the fact that heated grape 
juice contains pectins and gummy substances, and that the juice 
itself has a very marked viscosity. Of course, it is always possible 
to remove the suspended matter by filtration, but this is a very 
tedious operation, and it is doubtful whether it is worth the trouble. 
