Part 478

Fermentation may be prevented in either of two ways:

(1) By chemical methods, which consist in the addition of germ poisons or antiseptics, which either kill the germs or prevent their growth. Of these the principal ones used are salicylic, sulphurous, boracic, and benzoic acids, formalin, fluorides, and saccharine. As these substances are generally regarded as adulterants and injurious, their use is not recommended.

(2) The germs are either removed by {766} some mechanical means such as a filtering or a centrifugal apparatus, or they are destroyed by heat or electricity. Heat has so far been found the most practical.

When a liquid is heated to a sufficiently high temperature all organisms in it are killed. The degree of heat required, however, differs not only with the particular kind of organism, but also with the liquid in which it is held. Time is also a factor. An organism may not be killed if heated to a high temperature and quickly cooled. If, however, the temperature is kept at the same high degree for some time, it will be killed. It must also be borne in mind that fungi, including yeasts, exist in the growing and the resting states, the latter being much more resistant than the former. One characteristic of the fungi and their spores is their great resistance to heat when dry. In this state they can be heated to 212° F. without being killed. The spores of the common mold are even more resistant. This should be well considered in sterilizing bottles and corks, which should be steamed to 240° F. for at least 15 minutes.

Practical tests so far made indicate that grape juice can be safely sterilized at from 165° to 176° F. At this temperature the flavor is hardly changed, while at a temperature much above 200° F. it is. This is an important point, as the flavor and quality of the product depend on it.

Use only clean, sound, well-ripened, but not over-ripe grapes. If an ordinary cider mill is at hand, it may be used for crushing and pressing, or the grapes may be crushed and pressed with the hands. If a light-colored juice is desired, put the crushed grapes in a cleanly washed cloth sack and tie up. Then either hang up securely and twist it or let two persons take hold, one on each end of the sack and twist until the greater part of the juice is expressed. Next gradually heat the juice in a double boiler or a large stone jar in a pan of hot water, so that the juice does not come in direct contact with the fire at a temperature of 180° to 200° F., never above 200° F. It is best to use a thermometer, but if there be none at hand heat the juice until it steams, but do not allow it to boil. Put it in a glass or enameled vessel to settle for 24 hours; carefully drain the juice from the sediment, and run it through several thicknesses of clean flannel, or a conic filter made from woolen cloth or felt may be used. This filter is fixed to a hoop of iron, which can be suspended wherever necessary. After this fill into clean bottles. Do not fill entirely, but leave room for the liquid to expand when again heated. Fit a thin board over the bottom of an ordinary wash boiler, set the filled bottles (ordinary glass fruit jars are just as good) in it, fill in with water around the bottles to within about an inch of the tops, and gradually heat until it is about to simmer. Then take the bottles out and cork or seal immediately. It is a good idea to take the further precaution of sealing the corks over with sealing wax or paraffine to prevent mold germs from entering through the corks. Should it be desired to make red juice, heat the crushed grapes to not above 200° F., strain through a clean cloth or drip bag (no pressure should be used), set away to cool and settle, and proceed the same as with light-colored juice. Many people do not even go to the trouble of letting the juice settle after straining it, but reheat and seal it up immediately, simply setting the vessel away in a cool place in an upright position where they will be undisturbed. The juice is thus allowed to settle, and when wanted for use the clear juice is simply taken off the sediment. Any person familiar with the process of canning fruit can also preserve grape juice, for the principles involved are identical.

One of the leading defects so far found in unfermented juice is that much of it is not clear, a condition which very much detracts from its otherwise attractive appearance, and due to two causes already alluded to. Either the final sterilization in bottles has been at a higher temperature than the preceding one, or the juice has not been properly filtered or has not been filtered at all. In other cases the juice has been sterilized at such a high temperature that it has a disagreeable scorched taste. It should be remembered that attempts to sterilize at a temperature above 195° F. are dangerous so far as the flavor of the finished product is concerned.

Another serious mistake is sometimes made by putting the juice into bottles so large that much of it becomes spoiled before it is used after the bottles are opened. Unfermented grape juice properly made and bottled will keep indefinitely, if it is not exposed to the atmosphere or mold germs; but when a bottle is once opened it should, like canned goods, be used as soon as possible to keep from spoiling.

Another method of making unfermented grape juice, which is often {767} resorted to where a sufficiently large quantity is made at one time, consists in this:

Take a clean keg or barrel (one that has previously been made sweet). Lay this upon a skid consisting of two scantlings or pieces of timber of perhaps 20 feet long, in such a manner as to make a runway. Then take a sulphur match, made by dipping strips of clean muslin about 1 inch wide and 10 inches long into melted brimstone, cool it and attach it to a piece of wire fastened in the lower end of a bung and bent over at the end, so as to form a hook. Light the match and by means of the wire suspend it in the barrel, bung the barrel up tight, and allow it to burn as long as it will. Repeat this until fresh sulphur matches will no longer burn in the barrel.

Then take enough fresh grape juice to fill the barrel one-third full, bung up tight, roll and agitate violently on the skid for a few minutes. Next burn more sulphur matches in it until no more will burn, fill in more juice until the barrel is about two-thirds full; agitate and roll again. Repeat the burning process as before, after which fill the barrel completely with grape juice and roll. The barrel should then be bunged tightly and stored in a cool place with the bung up, and so secured that the package cannot be shaken. In the course of a few weeks the juice will have become clear and can then be racked off and filled into bottles or jars direct, sterilized, and corked or sealed up ready for use. By this method, however, unless skillfully handled, the juice is apt to have a slight taste of the sulphur.

The following are the component parts of a California and a Concord unfermented grape juice:

Concord California Per Per Cent Cent

Solid contents 20.37 20.60 Total acids (as tartaric) .663 .53 Volatile acids .023 .03 Grape sugar 18.54 19.15 Free tartaric acids .025 .07 Ash .255 .19 Phosphoric acids .027 .04 Cream of tartar .55 .59

This table is interesting in so far that the California unfermented grape juice was made from Viniferas or foreign varieties, whereas the Concord was a Labruska or one of the American sorts. The difference in taste and smell is even more pronounced than the analysis would indicate.

Small quantities of grape juice may be preserved in bottles. Fruit is likely to be dusty and to be soiled in other ways, and grapes, like other fruits, should be well washed before using. Leaves or other extraneous matter should also be removed. The juice is obtained by moderate pressure in an ordinary screw press, and strained through felt. By gently heating, the albuminous matter is coagulated and may be skimmed off, and further clarification may be effected by filtering through paper, but such filtration must be done as rapidly as possible, using a number of filters and excluding the air as much as possible.

The juice so obtained may be preserved by sterilization, in the following manner: Put the juice in the bottles in which it is to be kept, filling them very nearly full; place the bottles, unstoppered, in a kettle filled with cold water, so arranging them on a wooden perforated “false bottom” or other like contrivance as to prevent their immediate contact with the metal, this preventing unequal heating and possible fracture. Now heat the water, gradually raising the temperature to the boiling point, and maintain at that until the juice attains a boiling temperature; then close the bottles with perfectly fitting corks, which have been kept immersed in boiling water for a short time before use.

The corks should not be fastened in any way, for, if the sterilization is not complete, fermentation and consequent explosion of the bottle may occur unless the cork should be forced out.

If the juice is to be used for syrup, as for use at the soda fountain, the best method is to make a concentrated syrup at once, using about 2 pounds of refined sugar to 1 pint of juice, dissolving by a gentle heat. This syrup may be made by simple agitation without heat; and a finer flavor thus results, but its keeping quality would be uncertain.

The juices found in the market are frequently preserved by means of antiseptics, but so far none have been proposed for this purpose which can be considered entirely wholesome. Physiological experiments have shown that while bodies suited for this purpose may be apparently without bad effect at first, their repeated ingestion is likely to cause gastric disturbance.

«SPARKLING WINES.»

An apparatus for converting still into foaming wines, and doing this efficiently, simply, and rapidly, consists of a vertical steel tube, which turns on an axis, and {768} bears several adjustable glass globes that are in connection with each other by means of distributing valves, the latter being of silver-plated bronze. The glass globes serve as containers for carbonic acid, and are kept supplied with this gas from a cylinder connected therewith.

The wine to be impregnated with the acid is taken from a cask, through a special tube, which also produces a light pressure of carbonic acid on the cask, the object of which is to prevent the access of atmospheric air to the wine within, and, besides, to cause the liquid to pass into the bottle without jar or stroke. The bottles stand under the distributing valves, or levers, placed above and below them. Now, if the cock, by means of which the glass bulbs and the bottles are brought into connection, is slightly opened, and the desired lever is put in action, the carbonic acid at once forces the air out of the bottles, and sterilizes them. The upper bottles are now gradually filled. The whole apparatus, including the filled bottles, is now tilted over, and the wine, of its own weight, flows through collectors filled with carbonic acid, and passes, impregnated with the gas, into other bottles placed below. Each bottle is filled in course, the time required for each being some 45 seconds. The saturation of the liquid with carbonic acid is so complete and plentiful that there is no need of hurry in corking.

By means of this apparatus any desired still wine is at once converted into a sparkling one, preserving at the same time its own peculiarities of taste, bouquet, etc. The apparatus may be used equally well upon fruit juices, milk, and, in fact, any kind of liquid, its extreme simplicity permitting of easy and rapid cleansing.

«ARTIFICIAL FRENCH BRANDY.»

I.—The following is Eugene Dieterich’s formula for Spiritus vini Gallici artificialis:

Tincture of gallapples 10 parts Aromatic tincture 5 parts Purified wood vinegar 5 parts Spirit of nitrous ether 10 parts Acetic ether 1 part Alcohol, 68 per cent 570 parts Distilled water 400 parts

Mix, adding the water last, let stand for several days, then filter.