The Apple. Various

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СКАЧАТЬ tang. Afterwards, the alcoholic solution, in the presence of the organic matter, is subjected to what is called acetic fermentation; that is, the vinegar plant grows at the expense of the organic matter in the cider, and this beverage is converted into vinegar, containing acetic acid. It is a familiar fact that the change does not readily take place except when cider is exposed to the air, and this is shown to be true from a chemical standpoint, as the cider really is oxidized to make the vinegar; that is, it takes up oxygen from the air.

      The greater the proportion of sugar, the greater the quantity of alcohol, the stronger the vinegar will be. Grapes contain more than twice as much sugar as apples; hence, a wine that is made from them is stronger in alcohol than a cider made from apples. Cherries, as will be seen by reference to the table above, contain a large amount of sugar; hence their use in making cherry brandy, which contains a large per cent. of alcohol. It should be said, however, that in order to make brandy the cherry juice must be distilled. In this respect the process is similar to that employed in making apple brandy.

      After the juice has been extracted from the apples the pomace that remains is sometimes used as a fertilizer. This is valuable chiefly on account of the mineral salts contained in it. An analysis of the pomace shows that it contains: Water, 69.90 per cent.; ash, .71; albuminous substances, 1.58; fiber, 4.87; nitrogen, free extract, 21.24; fat, 1.71.

      The acid of the apple is usually considered to be malic acid, but really there are several acids mixed together. It is a mild and agreeable vegetable acid, and its presence adds much to the flavor of the fruit. The pectous and albuminous substances are those that assist in the formation of fruit jellies. Some of these substances are liquid when hot, and gelatinize on cooling; by too long boiling they lose this property of gelatinizing; hence the precaution that is taken in the making of fruit jellies not to boil the juice too long.

      The subject of the ripening of fruits like the apple has been extensively studied, as has also that of the subsequent decay. According to recent researches, early varieties of apples contain little starch when picked, and do not keep well. The season, soil, and age of the tree affect the composition of the fruit. It has been shown that sugar is sure to be formed from the starch in the process of ripening, after the fruit is taken from the tree, and during the winter the cane sugar is gradually, and finally almost entirely, changed to directly-reducing sugar. The maximum sugar content is reached earlier the earlier in the season the apple ripens. Late winter varieties reach this point as late as November. There is much starch in the latter when picked, which gradually changes to sugar on keeping. This process is analogous to the ripening of the banana. This fruit is picked while green, and from it is made by the natives of South America a flour which is a good farinaceous food, and readily answers the place of the starchy grains. We are familiar with the fact that as the fruit ripens it contains large quantities of sugar, and is edible uncooked, which fact is usually not true of starchy foods.

      The subject of the decay of the apple has been discussed in a very interesting way in the Popular Science Monthly for May, 1893, by Byron D. Halsted. Though chemical changes take place here, also, and the apple is finally resolved mostly into carbonic-acid gas, water, and mineral salts, yet these changes are brought about by the action of various fungi which find a soil favorable to their growth in the apple pulp.

      Though apples are considered digestible and wholesome, their digestibility is much increased by cooking. This is especially true if some of the starch is not converted to sugar, for, as noted above, starch, to be readily assimilated in the system, should be cooked. There is probably no fruit that is so uniformly wholesome and so deservedly popular with all classes as the apple. The apple and pear were known in England before the conquest, and, indeed, probably before the Saxon invasion. They have been gradually "improved" from the wild crab-apple of Europe. It is stated on good authority that there is no country on the globe so well adapted to the growth of this fruit as the temperate regions of North America, and this seems to be demonstrated by the fact that the apples of the United States are superseding the native fruit in most of the civilized countries.

      ANALYSES OF THE ASH OF THE APPLE.

	Sap-wood.	Heart-wood.
Potash	16.19	6.620
Soda	3.11	7.935
Chloride of sodium	.42	.210
Sulphate of lime	.05	.526
Phosphate of peroxide iron	.80	.500
Phosphate of lime	17.50	5.210
Phosphate of magnesia	.20	.190
Carbonic acid	29.10	34.275
Lime	18.63	35.019
Magnesia	8.40	6.900
Silica	1.65	.700
Organic matter	4.60	2.450
Totals	100.65	100.535

      

      ANALYSES OF APPLES.

      One hundred pounds of average apples contain the following:

      No. 1.

СКАЧАТЬ

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Fiber	3.2	lbs.
Gluten, fat, and wax	.2	"
Casein	.16	"
Albumen	1.4	"
Dextrine	.7	"
Sugar	8.3	"
Malic acid