It is the most abundant as well as the most valuable of fruits. The apple is grown practically in all parts of the United States, but there are some localities in which the apple tree flourishes in great abundance. Among the states which are famous for apple growing may be mentioned New York, Virginia, Michigan, and Missouri.

The varieties of apples are so numerous that it will be useless to attempt to mention them. Some of the most important are the Ben Davis, the Pippin, the Winesap, Jonathan, Rhode Island Greening, York, Albemarle Pippin, Clayton, Early Harvester, Sweet June, Tompkins King, Northern Spy, Russet, Yellow Bellflower, etc.

Acidity of Apples.

—One of the chief points in the palatability of apples as well as in their general character is their acidity. While apples are not relished when too sour they are as little relished when too sweet. The sugar and acid in apples are the chief factors in their palatability, not excluding the delicate flavor imparted by essential oils and ethereal substances which, though present in such small quantities as not to be measured chemically, nevertheless are highly important in making up the total effect of palatability and wholesomeness. The chief acid in apples is malic. It exists during all periods of the growth of the apple, but is more apparent in the green and immature state than in the ripe fruit. The relative quantity of malic acid in respect of sugar and starch is given under the heading of “Behavior of Apples During Storage.”

Adulteration of Apples.

—There is, of course, no adulteration of apples in their natural state except the attempt which is sometimes made to deceive the purchaser respecting the character of the whole package by placing the best and most attractive fruit on the top. This is such a well known practice, though regrettable, as not to demand any particular comment. The purchaser who has his own interest at stake will usually inspect the bottom as well as the top of the package before buying. The chief forms of debasement are those which are not practiced with any attempt to deceive. They consist in offering apples which are bruised by carelessness in gathering, or which are infected by insect life. In fact the greatest damage to which the apple is subject is that of the ravages of insects. There are certain kinds of insects which naturally breed in the apple. The egg is often laid in the early development of the fruit and by the time the apples are ready for consumption the larvæ stage has been reached and the worm has produced ravages to a great extent which are often not indicated by any external appearance. It is evident that the farmer cannot be held responsible in all cases for this condition of the fruit. Nevertheless it is only fair to state that in the modern development of the spraying industry the ravages of insect pests can be restrained and controlled, if not entirely prevented, by the proper spraying of the fruit. This spraying introduces another danger which cannot be forgotten, namely, the remaining upon the surface of the fruit of some of the spraying material itself. If present at all this material is apt to be either at the point of the junction of the stem with the fruit or at the opposite extremity of the apple. For this reason the fruit when eaten raw should be peeled in order that any remaining particles of the poisonous material used in spraying may be removed. It is to the interest of the merchant to present fruit of this kind in the most attractive form, by the exclusion of bruised, rotten, or infected apples and the offering of the sound, ripe fruit in as presentable a condition as possible.

Composition of Apples at Various Stages of Maturity.

—The following table shows the analysis made of one variety of apple, the Baldwin, at various stages of maturity:

Condition.Solids.Invert
Sugar.
Cane
Sugar.
Starch.Acidity as
Malic
Acid.
Per Cent.
Ash.
Percent.Percent.Percent.Percent.Percent.Percent.
Very green,18.476.401.634.141.140.27
Green,20.196.464.053.67........
Ripe,19.647.706.81 .17 .65 .27
Overripe,19.708.815.26None .48 .28

The chief point of interest in the above analysis is the gradual decline of the starch. When the apple is overripe the starch is entirely gone. When the apple is ripe only a small part of the starch is found. In the green apple very large quantities of starch are found. The sugar increases as the starch diminishes. There is a little over 14 percent of sugar in the perfectly ripe apple but much less in the green. The acidity calculated as malic acid diminishes as maturity is approached. In general it may be said that in the ripening of an apple the starch is converted into sugar and the acidity is diminished.