By-products Of Grape Industries

There are several valuable by-products in the wine-making and

grape-juice industries, and even raisin-making yields a by-product in

the seeds taken from the raisins. The utilization of these wastes has

been rendered profitable in Europe, and there is no reason why

by-products should not yield considerable profit in America, as a few

already do. Good authorities state that if all the wastes of the

grape crop could be ut lized the value of the crop would be increased

over 10 per cent.



Pomace.



The pomace or marc, the residue left after grape pressing, is the most

valuable of the by-products of the wine and grape-juice manufacturers.

If the pomace is permitted to ferment, and afterwards is distilled, a

product called pomace-brandy is made. Unscrupulous wine-makers often

add water and sugar to pomace, after which it is refermented and the

resulting product is sold as wine. Notwithstanding the fact that the

word "wine" as applied to this product is a misnomer, the total amount

of such wine made and consumed in America is large. Piquette is

another product in which the pomace is put into fermenting vats,

sprinkled with water and the liquid after a time is drawn off,

carrying with it the wine contained in the pomace. This liquid is

re-used in other pomace, until it is high enough in alcoholic

strength, when it is distilled into "piquette" or "wash."



In Europe, the pomace from stemmed grapes is said to make a sheep and

cattle food of more or less value when salted slightly and stored in

silos. The pomace is also oftentimes used as a manure, for which it

has considerable to recommend it, being rich in potash and nitrogen.

Acetic acid is made from pomace by drying it in vapor-tight rooms,

during which process 50 to 60 per cent of the weight of the pomace

becomes vapor, and this, condensed, yields considerable quantities of

acetic acid.



Cream-of-tartar.



The lees of wine, the sediment which settles in the casks in which new

wine or grape-juice is stored, form a grayish or reddish crust on the

inside of the receptacle. This is the argol or wine-stone of the

wine-maker, and from it is made cream-of-tartar, an article

considerably used in medicine, the arts and for culinary purposes.

From 20 to 70 per cent of the lees consist of either cream-of-tartar,

or of calcium tartrate, the latter also having commercial value. Red

wines are much richer in argol than white wines. A ton of grapes

yields from one to two pounds of argol. This product becomes a source

of considerable profit in large wineries and in grape-juice

manufacturing plants.



Seeds.



In Europe, the seeds are separated from the pomace and used in various

ways. They are also utilized to a smaller extent in America,

especially when separated from raisins. The seeds are used as food for

horses, cattle and poultry, for which they are said to have

considerable value. If crushed and ground, the seeds yield a clear

yellow oil which burns without smoke or smell and which may also be

employed as a substitute for olive oil. A ton of grapes yields from

forty to one hundred pounds of seeds from which may be made from three

to sixteen pounds of oil. This oil is also used as a substitute for

linseed oil and in soap-making. Besides oil, the seeds yield tannin.

After the oil and tannin have been taken from the seeds, there remains

a meal which may still be utilized as a stock food or as a fertilizer.