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Home and Farm Food Preservation
Chapter VII - Fruit Juices


Refreshing juices of pleasing flavor can be made from many fruits. The problem is one of so preserving the juice that as much as possible of its fresh flavor and appearance is retained. The most practical way of accomplishing this is by pasteurization by heat at temperatures from 150° to 180° F.

26. Fruits for Juice. Fruits for juice making should possess an agreeable flavor and aroma and be rather tart in taste. Very sweet fruits of low acid do not make attractive juices. Grapes should possess an agreeable flavor and high acid. A red color is preferred to white. The Eastern varieties have these qualities in a single variety. Two Californian varieties must be blended; one furnishing flavor and the other color and acid. Muscat, blended with any tart red wine grape, will give the desired result. Concord, Isabella, or other good Eastern varieties, used alone, give good results. The grapes should not be too sweet. A juice of 20% sugar and .8% to 1% acid is of the proper composition.

Loganberries make an excellent juice. They should be as ripe as possible.

Blackberries, raspberries, and strawberries make rather poor juices.

Apple juice is used in great quantities fresh, but a relatively small amount is pasteurized, largely because apples may be obtained practically throughout the whole year for the production of fresh juice.

Orange and lemon juices have not been successes commercially, because of the difficulty in retaining the flavor of the fresh juices.

Pomelo or grape fruit juice has been developed commercially in Florida.

Pineapple juice as now found on the market is attractive in appearance, but very disappointing in flavor.

Pomegranates produce a highly colored juice of fair flavor, but there is considerable difficulty in separating the juice-bearing seeds from the astringent pulp.

Grape, apple, loganberry, and pomelo juices are all easily prepared and are all of very satisfactory quality. Other fruits may prove satisfactory sources of juice as methods of preparing the juice are developed by investigation.

27. Crushing. To facilitate heating of the fruit before pressing and the extraction of the juice the fruit must be thoroughly crushed.

In the household a small food chopper or small fruit crusher may be used. (See Fig. 20.) Small hand power crushers are available for farm use. (See Fig. 22.) Larger crushers for factory use are of many types, sizes, and prices. Grape crushers consist of two wooden or iron cylinders revolving closely enough together to crush the fruit but not the seeds. It is desirable to separate the sterns from grapes after crushing. This is done by mechanical stemmers or by hand by use of a coarse screen.

28. Heating before Pressing. The color of grapes must be dissolved from the skins by heating. Berries will press more satisfactorily if heated. Citrus fruits, pomegranates, and apples should not he heated.

The crushed grapes should be heated to about 120° to 135° F. by use of an aluminum or agateware pot. They should be stirred frequently and the temperature observed carefully with a dairy or other type of thermometer, that can be conveniently immersed in the crushed grapes. Grapes are allowed to stand twenty-four hours before pressing to permit the color to dissolve in the juice. The grapes may also be heated by separating the juice by pressing and heating it to, 140 to 150° F. and returning it to the skins.

Berries should be heated to about 150 to 165° F. and pressed hot.

29. Pressing. The simplest press is a heavy cloth bag which may be twisted. Small kitchen presses may be had also. Various sizes and forms of presses suitable for farm and factory use may be had. The hydraulic press is the most commonly used commercial press and gives the highest pressure of any fruit press.

Pressure is applied directly to the fruit in the "basket" form of press. In the rack and cloth type the fruit is held between layers of heavy press cloths. Wooden racks separate the cloths. This type of press gives a clearer juice than the basket press but requires more labor.

30. Clearing the Juice. The juice comes from the press cloudy—not perfectly clear. It also contains proteins in solution which, if not removed, are coagulated during pasteurization later and cause the juice to become cloudy. Therefore, to produce a juice which will be clear and remain so in the bottle, it must be heated to the temperature at which the juice is to be pasteurized later and must then be filtered or otherwise cleared. The juice will then clear more satisfactorily if it is allowed to stand overnight after pressing and before clarifying. After standing this length of time it may be drawn off from the sediment and cleared in any way desired.

The juice may be clarified by the addition of egg white, casein, or Spanish clay before heating. These materials are coagulated and settle out after heating, carrying down with them the suspended particles which have caused the juice to be cloudy. Grape juice may be clarified by any of the above materials used singly; or with casein or egg white employed in combination with the clay. Other juices are best clarified by the use of the clay only. Casein may be bought from a drug store or chemical supply house. Spanish clay may be obtained from chemical supply firms.

The casein is prepared for use by boiling together three ounces of casein to one ounce of sal soda in one quart of water. When dissolved, this is diluted to one gallon with water. Spanish clay is prepared for use by soaking a weighed amount in a measured amount of water until soft. One gallon of water is used for each pound of clay. When soft it is worked into a thin, even-grained mud with the water. Egg white is mixed with several times its volume of water and stirred until dissolved. Dried albumen may also be used.

In using the clarifying materials described above, the amount necessary is measured and added to the juice and mixed thoroughly by stirring.

The juice is then heated to 175° F. and allowed to stand twenty-four hours. Most of the juice can then be poured off clear from the sediment or filtered easily through a jelly bag.

It must be emphasized that clarification is not necessary for the preservation of the juice, and results in some loss of flavor. It is not generally recommended for home use. It is only necessary in the home production of juice to heat it to 175° F. allow it to cool twenty-four hours, and filter through a jelly bag.

The juice may be filtered through a felt filter bag specially made for small scale filtration or through an ordinary cloth bag. Filter bags vary in size from one to ten gallons and cost from one and one-half to ten dollars. Larger metal filters that are filled with asbestos or wood fiber are used in large scale filtration, but cost very much more.

A box filled with sand also makes a fairly satisfactory filter. A funnel fitted with filter paper can also be used.

Filters must be thoroughly washed after use to prevent souring. Juice is ordinarily difficult to filter, unless clarified, and the filters must be changed and cleaned often during continued filtration to maintain them at full capacity.

For home use a rough filtration without a clarification is all that is required.

31. Bottling and Canning. The previous operations have prepared the juice for the final container in which it is to be stored. Bottles, jars, and cans are all used as containers. These should be clean.

Two types of bottles are available: those with plain tops to be closed with corks and those with special tops to be closed with caps or crowns. The bottles should not be filled completely and a space of about an inch and a half should be left between the cork and the juice.

If the bottles are to be corked, the corks must be sterilized in boiling water for ten minutes before they are used. Ordinary taper corks of good quality may be used, but wine bottle corks driven into the bottles with an inexpensive apparatus designed for the work give better results.

The corks must be tied down with a string to hold them in place during pasteurization.

If crown finish bottles such as soda water, beer, or grape juice bottles are used, the crowns or caps are crimped on by a special machine. This costs from five dollars upward. The crowns cost about thirty cents per gross and are cheaper and more attractive in appearance than corks. If any great amount of juice is to be put up, their use is recommended.

Cans may be used for the less acid juices, such as grape and apple juices, but are not recommended for very acid berry or lemon juice, because of the danger of the solution of tin in poisonous quantities. Enamel lined cans are best and sanitary cans are to be preferred to solder top cans because of the danger from the action of the juice on the solder used in sealing the latter.

Cans may be filled with hot juice at 180° F. and sealed at once without further sterilization. A better plan is to fill them with warm (not hot) juice, seal, and then pasteurize.

Jars may also be used. They are filled with the warm juice and sealed at once with scalded caps and rubbers. The juices are pasteurized in the jars.

32. Pasteurization of Fruit Juices. Fruit juices must not be overheated but nevertheless they must be heated to a high enough temperature to insure their keeping. This temperature is between 165° and 170° F. The temperature must be maintained for about twenty minutes. Juice should never be boiled.

The most convenient and certain way of obtaining these conditions is to heat the bottles or cans while they are completely immersed in water.

An ordinary wash boiler with a false bottom makes a satisfactory pasteurizer; or any of the factory-made home and farm sterilizers may be filled with water and used as pasteurizers.

See Fig. 25. A larger pasteurizer may be made of a wooden tank and steam coils as indicated in Figs. 26 and 27.

The sealed jars, bottles, or cans, are placed in the pasteurizer and completely covered with water. Bottles should lie horizontally so that the hot juice will sterilize the corks. With a thermometer inserted in the water, it is heated to 175° F. and maintained at this temperature for twenty minutes. The temperature in the containers will be several degrees below 175° F. The bottles or cans are then removed. The necks of corked bottles should be dipped in paraffin or sealing wax as soon as removed and again when cool. Bottles closed with crown caps need not be so treated.


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