Grape-juice

When properly made, grape-juice is the undiluted, unsweetened,

unfermented juice of the grape and contains no preservatives,

fermentation being prevented by sterilization with heat. The product

is as ancient as wine, and, therefore, as the cultivation of the vine,

for all wine-making peoples have used new wine or grape-juice as a

beverage. For centuries physicians in wine-making countries have

prescribed grape-juice as it comes from the wine-press for certain

maladies, the treatment constituting an essential part of the

grape-cures of European countries. The process of making an

unfermented grape-juice that will keep from season to season as an

article of commerce is, however, a modern invention, and is the

outcome of the discoveries of the last half century regarding the

control of the agents of fermentation.



The manufacture of commercial grape-juice in America, to which country

the industry is confined, began as a home practice following the

fundamental processes of canning fruit. Toward the close of the last

century, several inventive minds discovered methods of making a

commercial product and began developing markets for their wares. The

beginning of the present century found the new industry in full swing,

since which time its growth has been truly marvelous. In 1900 the

amount of grape-juice made in the United States was so small as to be

negligible in the census report of that year. By 1910, the annual

output had reached for the whole country over 1,500,000 gallons and at

present writing, 1918, it is well above 3,500,000 gallons per annum.

The manufacture of grape-juice is no longer a home industry but a

great commercial enterprise. It is an industry closely associated with

grape-growing, however, and as such needs further consideration here.



Grape-juice regions.



The manufacture of grape-juice is centered in the Chautauqua

grape-belt in New York, Pennsylvania and Ohio. So far, the demand

seems to be almost wholly for juices made from native grapes, the

juice of European grapes grown on the Pacific slope being so sweet as

to be insipid. Possibly 80 per cent of the grape-juice now

manufactured in America comes from a single variety, the Concord.

There can be no question, however, but that sooner or later

grape-juices of distinct qualities will be made from many varieties of

grapes, thus giving wider sale and greater variation for the product.

A very good sparkling grape-juice is now on the market and its

reception seems to promise a great increase in the production of an

article that closely simulates champagne in color and sparkling

vivacity, but not, of course, in taste, since it contains no alcohol.

The grape-juice industry has been started and is in a flourishing

condition in several other grape regions than the Chautauqua belt

which is now its center. There are factories at Sandusky, Ohio, using

grapes grown in the Kelly Island district; in southwestern Michigan

there are several factories; and the industry still survives at

Vineland, New Jersey, which probably should be called the original

home of the manufacture of grape-juice. In the South, some grape-juice

is made from Muscadine grapes, but this product seems not as yet to

have been well received in the markets.



Commercial methods of making grape-juice.



There is at present a great diversity of methods and of apparatus

employed in the grape-juice manufacturing plants throughout the

country. Since the industry is in its infancy, and the attempt has

been made to hold some of the methods as trade secrets, the diversity

of methods and appliances is not to be wondered at. No doubt there

will be greater uniformity of method and machinery and, therefore,

greater efficiency, as the industry develops.



Husmann[19] gives the following account of the manufacture of

grape-juice in the eastern states and in California:



"Sound, ripe, but not over-ripe, grapes are used. These are first

crushed or, in case the stems are to be removed, are run through a

combined stemmer and crusher. If the machinery is stationed high

enough, the crushed fruit can be run through chutes directly into the

presses or kettles; otherwise, it must be pumped into them by means of

a pomace or must pump or carried in pomace carts or tubs.



"If a white or light colored juice is desired, the crushed grapes are

first pressed, the juice which comes from the press being heated to

about 165 deg. F., skimmed, run through a pasteurizer at a temperature of

between 175 deg. and 200 deg. F. into well-sterilized containers, and then

placed in storage.



"If a colored juice is desired, the crushed grapes are heated

immediately, usually in aluminum kettles having double bottoms, which

prevent the steam from coming in contact with the contents. These

kettles usually contain revolving cylinders, the arms of which keep

the crushed grapes thoroughly stirred while they are being heated to

about 140 deg. F. The simultaneous heating and stirring help to extract

the coloring matter from the skins, tear the cells of the berries,

increase the quantity of juice obtained per ton of fruit, and give to

the must many ingredients of red wine, with the substitution of grape

sugar for alcohol of the wine.



"The aluminum kettles are filled and emptied in rotation, thereby

making continuous manipulation possible. The presses should be

situated below the kettles, so that the hot juice can be drained

directly into them. The expressed juice is then reheated to about 165 deg.

F., skimmed, and run through the pasteurizer in the same manner in

which the white juice is handled. The juice passes from the

pasteurizer while still hot (about 160 deg. F.) into the container, which

should be sealed immediately. The lower the temperature (above the

freezing point) at which these containers are then stored, the less is

the danger of fermentation and the more rapidly the juice will clear

and deposit its sediment.



"The ordinary receptacles in which the juice is stored are 5-gallon

demijohns, 20-gallon carboys, or clean, new barrels or puncheons, well

washed and drained. All containers should be thoroughly sterilized

before they are filled, and the covers, corks, bungs, cloths, etc.,

used in sealing them should be scrupulously clean and carefully

sterilized. If barrels or puncheons are used as containers, they are

placed on skids and firmly wedged to prevent movement. As the juice

cools, air laden with fermentation germs is apt to be drawn into the

barrels by the decrease in the volume of the liquid. In order to

prevent this, tight air-filtering plugs of sterilized cotton are

sometimes used instead of the ordinary bungs of solid wood.



"The type of pasteurizer differs in almost every establishment. As the

industry is of comparatively recent development commercially, there

are few models on the market and each manufacturer has constructed the

model best suited to his particular ideas or requirements. There are

two general types, however, (1) open, double-bottomed kettles in which

the juice is heated to the required temperature and then drawn off,

and (2) continuous pasteurizers in which the juice is heated to the

required temperature as it passes through the water bath.



"The presses also show great variation in different establishments,

either hydraulic, screw or lever power being used, and there is a

marked difference between the types of pomace containers. Sometimes

the crushed grapes are heaped on burlap cloths the sides of which are

folded in, and these burlaps are placed one on top of the other in the

press; sometimes press baskets take the place of these burlaps.



"The manufacturers in California and those in the grape-growing

regions of the Rocky Mountains seem to have adopted entirely different

methods of handling the juice after it is first pasteurized and

stored. Most of the eastern juices are red and are obtained from the

Labrusca varieties, generally the Concord. When the juice comes from

the presses, some manufacturers strain it to remove the coarse

particles and then pour it directly into well-sterilized bottles;

others siphon it off the sediment in the containers in which it is

stored after the first pasteurization and pour it into pasteurized

bottles. In either case, the bottles are securely corked and then

repasteurized. The California juices, however, both red and white, are

made exclusively from Vinifera varieties. They are allowed to settle

in the original containers and are siphoned out of these and carefully

filtered to make them clear and bright.



"The clearing of the juice is sometimes facilitated by fining or

adding a small quantity of a substance which coagulates and when

settling carries down with it the solid matters causing cloudiness in

the liquid. Such finings may be applied at the time of the first

pasteurization or just before the final filtration and bottling. In

the latter case the juice is drawn off the settlings in containers,

the finings are added, and the juice again pasteurized into other

receptacles. When it clears, it is either bottled directly or first

passed through a filter, drawn into carefully sterilized bottles,

securely corked, and then repasteurized. Care must be taken that the

final sterilization is not at a higher temperature than the previous

one; otherwise, solid matter may be precipitated and the must clouded

again.



"A simple and efficient form of sterilizer consists of a wooden trough

provided with a wooden grating which is raised 2 inches from the

bottom and on which rest the filled bottles in wire baskets. The

trough contains enough water to submerge the bottles and is kept at a

temperature of 185 deg. F. by means of a steam coil beneath the grating.

It requires about 15 minutes for the must at the bottom of the bottles

to reach that temperature; for packages of other sizes it is necessary

to make a test with a thermometer in order to determine how long it

takes for the entire contents to reach 185 deg..



"To prevent the corks from being expelled during sterilization, they

are either tied down with a strong twine or with some contrivance such

as the cork holder. In order that mold germs may not enter the must

through the corks, especially if a poor quality of cork is used, the

necks of the corked bottles are dipped in heated paraffin before

putting on the caps, or the corks are sealed down with sealing wax. It

is also well to keep the bottles on their rider to prevent the corks

drying out."



Home methods of making grape-juice.



The principles involved in making grape-juice in the home are the same

as those used in canning. The grapes may be crushed by hand or in

mills similar or identical with the small cider-mills owned by many

farmers. In making a light-colored juice, the crushed grapes are put

in a cloth sack and hung up to drain, or the filled sack may be

twisted by two persons until the greater part of the juice is

expressed. The juice is then sterilized in a double-boiler by heating

it at a temperature of 180 deg. to 200 deg. F., care being taken that the

thermometer never goes above 200 deg.. The sterilized juice is now poured

into a glass or enameled vessel to stand for twenty-four hours, after

which it is drained from the sediment and strained through several

thicknesses of clean flannel. The juice is now put in clean bottles

preparatory to a second sterilization, care being taken that at least

an inch of space is left at the top for the liquid to expand when

heated. The second sterilization may be conducted in a wash-boiler or

similar receptacle. The filled bottles must not rest on the bottom of

the boiler but should be separated from it with a thin board. The

boiler is filled with water up to within an inch of the tops of the

bottles and heated until the water begins to boil. The bottles should

then be taken out and corked immediately, using only new corks. After

corking, the bottles are further sealed by dipping the corks in melted

paraffin. A cheap corking machine is a great convenience in this work,

and in any case the corks should be soaked for at least a half hour in

warm but not boiling water.



The process varies somewhat in the making of red grape-juice. The

crushed grapes are heated to a temperature of 200 deg. F., and are then

strained through a drip bag without pressure, after which the liquid

is set away in glass or enamel vessels to settle for twenty-four

hours. Except for this difference in the preliminary treatment of the

juice, the methods are the same in making the red or the light-colored

product. For proper keeping it is not necessary to let the juice

settle after it is strained, but a clearer and brighter product is

obtained if the juice is permitted to settle. In either case the

grape-juice should keep indefinitely if the work has been well done.

As soon as bottles are opened, fermentation begins with the formation

of alcohol.