Foods and Their Adulteration / Origin, Manufacture, and Composition of Food Products; Description of Common Adulterations, Food Standards, and National Food Laws and Regulations

by Harvey Washington Wiley

Small Fruits.

Blackberries (Rubus nigrobaccus var. Sativus Bailey).

—Among the small fruits one of the most common and abundant is the blackberry. This fruit grows wild over large areas in the United States, mostly in the middle portion between the extreme north and south. The brier on which it grows is an annual plant, springing each year from the roots and dying after bearing fruit. The plant is very largely cultivated, bearing larger and more presentable berries, but gaining nothing in flavor and palatability. The berries are generally black when fully ripe, though red during the ripening stage and sometimes when mature. They are eaten raw, stewed, and in pies or “cobblers.” The berry is extensively used for making jams, jellies, and preserves, and for canning purposes. The juice of the berry is used for making a wine, usually with the admixture of sugar. Blackberry cordial is blackberry juice preserved in whisky or brandy.

Dewberry.

—This is a variety of blackberry in which the vines lie on the ground instead of standing upright. Some of the dewberries possess unusual fragrance and palatability. In other respects they conform to the statements relating to blackberries.

Gooseberry (Ribes oxyacanthoides L.).

—The gooseberry resembles very closely the currant in its general properties. In the European gooseberry the surface is covered with prickles, but the American variety is smooth. The gooseberry bush is found in most gardens, affording a fruit of high condimental value. The fruit is eaten raw, but principally in pies and as preserves.

Huckleberry (Gaylussacia resinosa Torr. and Gray).

—The fruit of the huckleberry bush is used very extensively for making pies, especially in the northeastern parts of the United States. There are many varieties of the berry on the markets. The blueberry is one variety that is very abundant. The term whortleberry is also applied to this fruit.

Mulberry (Morus nigra).

—The mulberry grows wild over extensive areas in the United States, especially in the Ohio valley. It is a tree valued highly for its wood, which is lasting and excellent for fence-posts. The berries ripen early in the summer or late in the spring and are used as food to a limited extent.

Raspberry (Rubus strigosus Michx.).

—The raspberry is nearly related to the blackberry in all of its characters. It is chiefly a cultivated plant, being less hardy than the blackberry, and therefore not growing wild to such an extent. The fruit matures just before the blackberry, and is usually of a red color and of a pleasant characteristic taste.

Strawberry (Fragaria Chiloensis Ehrh.).

—For edible purposes in its fresh state the strawberry is the most important of the small fruits. It is offered on the markets at all seasons of the year—ripening in the winter time in Florida and California and coming into the markets in the late summer in the northern and northeastern states. It grows on vines lying on the ground and ripens early in the spring in the latitude of Washington, viz., from about the middle of May. It is eaten raw—often with sugar and cream—more extensively than any other small fruit. The wild strawberry is not so large as the cultivated variety, but is more highly prized for its aroma and taste.

Composition of Small Fruits.—

	Water.	Protein.	Fat.	Sugar, Starch Etc.	Ash.
	Percent.	Percent.	Percent.	Percent.	Percent.
Blackberries,	86.3	1.3	1.0	10.9	0.5
Cranberries,	88.9	0.4	0.6	9.9	0.2
Huckleberries,	81.9	0.6	0.6	16.6	0.3
Raspberries,	84.1	1.7	1.0	12.6	0.6
Strawberries,	85.9	0.9	0.6	7.0	0.6

Tropical and Subtropical Fruits.
(Bulletin 87, Bureau of Chemistry.)

Anona.

—This is a variety of edible fruit grown in the tropics, especially in Cuba, but on account of its restricted production is of little importance. There are three varieties, known as follows: Sweet-sop (anona) (Anona squamosa L.), sour-sop (guanabana) (Anona muricata L.), and custard apple (chirimoya) (Anona reticulata L.). The sour-sop is a green, irregular-shaped, pod-like fruit, varying from 3¹⁄₂ inches to 12 inches in length and about two-thirds as broad near the top, and curving to a blunt point at the lower end. The skin is thick and covered with numerous small, hooked briers. The pulp has the appearance of wet cotton and surrounds the numerous seed sacs containing the small brown seeds. A fibrous core runs through the fruit from the stem to the lower point. The fruit weighs from 3.5 ounces to 2.2 pounds. The flavor is acid, but not too much so. This fruit is more extensively used in the manufacture of cooling beverages than directly as a food, but it is also used very extensively for making preserves. The sweet-sop resembles the sour-sop in general character, but does not attain by any means to so large a size. The fruit is heart-shaped and deeply creased. The pulp contains more sugar and less acid than that of the sour-sop. This variety is eaten fresh and is also used for flavoring beverages, but is not extensively used for making preserves. The third variety, known as the custard apple, varies in color from light green to reddish brown, and is shaped something like a strawberry. It has a thick skin and black seeds, and a pulp very similar to that of sweet-sop in flavor. It is eaten chiefly raw, and is not very extensively used in the manufacture of preserves.

Composition of the Sour- and Sweet-sop Varieties.—

	Edible Portion.	Solids.	Total Sugar.	Protein.	Ash.	Acidity.
	Percent.	Percent.	Percent.	Percent.	Percent.	Percent.
Sour-sop,	72.30	19.03	13.07	1.65	.41	.51
Sweet-sop,	30.00	28.10	10.07	2.13	.92	.20

The above analyses show that the anona is a fruit which has about half the nutritive value of the banana. It has a much larger percentage of waste, especially the sweet-sop variety, where nearly three-fourths of the fruit is not edible.

Anona Preserves.

—The anona preserves should be made exclusively with sugar and thus have the character of the fruit modified only by the amount of sugar added. In one sample of preserves analyzed the following data were obtained:

Total solids,	54.33	percent
Total sugar,	49.66	„
Protein,	.73	„
Ash,	.43	„
Acidity,	.19	„

The above data show that the natural constituents of the fruit have been diminished in quantity in proportion to the amount of sugar added.

The Avocado (Persea persea).

—The avocado is a fruit which has only lately been introduced into the United States. Its common name is alligator pear and it is already very highly prized.

The cultivation of the alligator pear was first undertaken as a novelty, and its real value as a dessert fruit is only beginning to be appreciated. It is evident that this fruit will have a great vogue in the near future, and will be in much demand as soon as its production is on a scale which makes it accessible to the people of ordinary means. The edible part of the fruit is a sweet, soft substance with an agreeable taste and of a semi-solid consistence. It has a nutty and peculiar flavor which is highly prized.

In the regions where the alligator pear is grown it is often used in the raw state or after having been treated with a little salt. It is highly prized when served in this manner. It is also often cut into small pieces and put into soup and is said to give a most agreeable odor and flavor thereto. The ripe fruit has different colors; it may be green, yellow, brown or dark purple or a combination of any of these colors. The alligator pear is particularly valued as a salad fruit.

Composition of the Avocado.—

Water,	81.10	percent
Protein,	1.00	„
Fat,	10.20	„
Starch and sugar,	6.80	„
Ash,	.90	„

The above data show that the alligator pear is not a fruit which is very highly nutritious. Its principle nutrient is fat, the next most important being starch and sugar, but it is extremely deficient in protein, and therefore could not be regarded as a balanced ration. Its principle value, therefore, is mostly on account of its condimental properties rather than for its nutrients. Bulletins 61 and 77 of the Bureau of Plant Industry, Department of Agriculture, give important information regarding the avocado. The accompanying [illustration] is taken from Bulletin 77, above mentioned.

From the amount of fat in the alligator pear it might be regarded as a nut instead of a fruit, but its paucity of nitrogenous constituents excludes it from that category.

Bananas (Musa).

—One of the most abundant and most important of the tropical fruits, for food purposes, is the banana. The banana is not grown to any extent for food purposes in the United States, though it is produced on a limited scale in southern Florida. Immense quantities of bananas come into this country from the Central American states, particularly from Guatemala and Nicaragua. This fruit can be landed at New Orleans at very small expense for transportation, and for this reason can be distributed all over the country at a price which looks to be ridiculously small when it is considered that the fruit comes from so great a distance. It is also sent in large quantities to other ports, notably New York, Boston, and Baltimore. For shipping purposes the banana is gathered while still green, and often the ripening has not reached the stage when the ordinary yellow color which characterizes the ripe fruit is seen when it reaches the markets in the center of the country. The banana is not only valued for its peculiar flavor, which is pleasant and sweet, sometimes almost too much so, but it also has a high nutritive value, being a substance rich in carbohydrates and growing in such abundance that its price is within the reach of the poorest classes. Great quantities of bananas are also grown in Cuba, but they are mostly consumed by the native population, forming one of the principal foods of the island.

Fig. 50.—Avocado Tree.—(Courtesy Department of Agriculture.)

The banana has perhaps less waste than almost any other fruit, as the whole of the inner portion is edible. In the green fruit there is a large proportion of starch, which gradually changes into invert sugar in the ripe fruit. In thoroughly mature bananas the quantity of sugar is relatively high and the quantity of starch correspondingly low. Bananas are not only eaten raw but also fried and in various other forms. The banana is a fruit which, when properly cared for, can be transported over long distances and kept for a long time. When properly prepared the banana forms a nutritious diet, probably equal in value to the same amount of solid matter contained in the common fresh fruits. One hundred grams may be taken as the average weight of the banana, although some of them are very much larger. About 70 percent of the banana is edible and 30 percent inedible, that is, the skin, which while not wholly inedible is usually rejected. The banana is essentially a carbohydrate food, the percentage of protein not usually rising above 1.3. Nearly all the carbohydrates in the ripe fruit consist of sugars which are present both as reducing and as cane sugars. The average total percentage of sugar present in the banana is a little over 20.

The composition of the banana is shown in the following table which contains the data of analyses of two samples bought in the open market in Washington.

	Edible Portion.	Solids.	Total Sugars.	Protein.	Ash.
	Percent.	Percent.	Percent.	Percent.	Percent.
Sample 1,	62.10	26.13	21.71	1.13	.84
Sample 2,	64.50	26.24	21.76	1.21	.86

The analytical data were obtained upon the edible portion and not upon the whole fruit.

The bananas which are imported from Jamaica and Central America are represented by the analyses given above. They are commonly known as the Johnson banana. Smaller fruits with better flavors are grown in Cuba,—some of them are of a red color like the oronoco and colorado. The indiano is a large, yellow, angular fruit with a salmon-colored pulp and a rather disagreeable acid flavor.

With reference to the banana as a food product it is seen that, including the starch and digestible cellulose, it consists of at least 25 percent, in its edible portion, of carbohydrates suitable for food purposes. Its low content of protein indicates that it is not a well balanced ration, but should be eaten in connection with beans, peas, or other vegetables rich in protein, or with lean meat in order to secure a proper quantity of protein in the diet.

On account of the great abundance of the product and luxuriance of growth in the Central American states, it is evident that the banana might become a profitable source of industrial alcohol in that locality.

Cashew (Maranon) (Anacardium occidentale).

—The cashew, of which the principal habitat is Cuba, is a small, oddly shaped, yellow and red fruit from two to three inches long and from ¹⁄₂ to two inches in diameter at the bottom, decreasing gradually in diameter toward the top. The seed is small and kidney-shaped and grows outside of the fruit at the lower end. The seed is regarded as poisonous until it has been roasted, due probably to the presence of hydrocyanic acid. After roasting it is regarded as a delectable edible. The meat of the seed of the cashew resembles the roasted chestnut, but contains more oil. The pulp is of a dull yellow color, is tough and very juicy, with an acid astringent flavor and a disagreeable odor. The fruit is not eaten raw but chiefly in preserves. The composition of the cashew is shown in the following table:

Composition of Edible Portion

—85.9 percent.—

Solids,	12.84	percent
Sugar,	6.76	„
Acid,	.31	„
Ash,	.36	„

The composition is somewhat like that of the hicaco, but the cashew contains a larger proportion of acid and hence is better suited for preserves. The sample of cashew preserves examined had the following composition:

Solids,	71.22	percent
Sugar,	66.89	„
Protein,	.26	„
Acidity,	.08	„
Ash,	.14	„

Citrus Fruits.

—The term “citrus fruit” is applied to that class of fruits represented by the orange, lemon, grape fruit, and lime. In the United States extensive areas are devoted to the production of citrus fruits, and it is claimed by connoisseurs that some of the best varieties grown anywhere in the world are the products of this country. Florida and southern California are two localities where the development of the citrus fruit industry has been carried to the greatest extent. The phenomenally cold winter which occurred in Florida some ten years ago almost ruined the citrus fruit industry in that state for the time being. In the reëstablishment of it the center of production has been extended farther south than it was before. It is believed that at the present time the industry has been extended sufficiently far south in the Florida peninsula to avoid any repetition of the great disaster which ruined the citrus groves in certain portions of the state at the time mentioned. The climate of southern California is more equable, and no injury has ever been experienced in that location from very low temperature. In Florida the oranges are cultivated without irrigation, while in southern California irrigation is universally practiced. The seasonal conditions are therefore under better control in California than in Florida.

Drying Figs

1. SMYRNA

2. SMYRNA SECTION

3. ADRIATIC

4. ADRIATIC SECTION

From Yearbook, U. S. Dept. of Agriculture, 1897

Figs (Ficus carica L.).

—The fig is a fruit which is well known in biblical and profane history. Together with the grape it is the fruit which is most often mentioned in the Bible.

The importance of the fig as a fruit and food is recognized in all the earlier writings, both sacred and profane. When dried and pressed into convenient forms it is a food which can be easily transported, and makes a ration well suited to supply heat and energy, although deficient in nitrogen in so far as a complete ration is concerned. The fig tree is extensively cultivated in all localities where the temperature permits its growth. It grows in the open in the whole southern part of the United States, and I have seen fig trees of large size grow in the yard as far north as Washington.

The fig tree grows luxuriantly and to a great size in California, and the fruit, both fresh and dried, is of superior excellence. A typical illustration of a California fig tree is shown in [Fig. 51].

The Smyrna fig has lately been introduced into the southern and western part of the United States with great success. It grows especially well in the southern part of California and Arizona. The Smyrna fig is one of the varieties which requires fertilization of the flower through the mediation of an insect. This process is called caprification. Although this variety of fig has only been introduced into California to any extent in the last five or six years, the growth of this most highly esteemed variety has so increased that at the present time the output of California alone amounts to about twelve million pounds per annum. The Smyrna and Adriatic figs, used largely for drying and preserving purposes, are seen in their natural colors in the appended colored plate.

Composition of Fresh Figs (Edible Portion).—

Water,	79.11	percent
Protein,	1.52	„
Sugar,	15.53	„
Pure ash,	.58	„
Fat, fiber, etc.,	3.26	„

Composition of Dried Figs.—

Water,	28.78	percent
Total sugar,	51.43	„
Acid as malic,	.71	„
Protein,	3.58	„
Ether extract,	1.27	„
Cellulose, etc.,	5.29	„
Crude fiber,	6.19	„
Ash,	2.75	„

Fig. 51.—Fig Tree Thirty Feet High near Yuba, California.—(Photograph by H. W. Wiley.)

The interesting process of caprification is thus described by Professor Hugh N. Starnes of the Georgia Experiment Station:

“In the base or false ovary of the gall flowers, which are merely degenerate pistillates, the egg of the Blastophaga grossorum or fig wasp—a minute insect—is deposited and develops to maturity. The wingless males emerge first and, with their powerful mandibles, cut into the flowers containing the female wasps, partially release them, and impregnate them. The gravid females shortly complete the liberating process and, being winged, at once seek to escape for the instinctive purpose of laying their eggs. They emerge from the eye of the caprifig, after squeezing through the mass of pollen-covered anthers protecting the exit, and seek other fruit in which to lay their eggs. Naturally they would enter the nearest caprifig in the proper stage of development. But, meanwhile, if the caprifig containing the colony has been plucked from its stem and suspended in the branches of an adjacent Smyrna tree, the female on emerging forces her way in a fruit of the latter class, losing her wings in the process, and at once begins a frantic scramble around the interior, searching for the anticipated gall flowers in which to deposit her eggs. Failing, necessarily, to find them, and incapable of again taking flight, she finally curls up and dies heartbroken, but not until she and her companions have between them pollinated every female flower in the cavity with the plentiful store of pollen conveyed from the caprifig—thereby insuring the development of the fruit.”

Grape Fruit (Pomelo) (Citrus decumana).

—The so-called grape fruit or pomelo is one of the biggest products of the citrus family and also possesses properties which may be regarded as a cross between the lemon and the orange. It is more acid than the orange and more sweet than the lemon. This fruit is perhaps more highly esteemed than any other citrus variety for direct edible purposes, forming a breakfast dish which is eaten very extensively throughout all parts of the United States by those who are able to afford the luxury, for so it still is by reason of the high price of the product. Grape fruit grows to a large extent in the United States, and its culture is confined to the same region as that where the orange and lemon are grown.

Composition of Grape Fruit (Pomelo).

—The composition of the pomelo as given for the California product (Station Report, 1892, p. 256) shows this fruit to have the following composition:

Average weight,	357.00	grams
Rind,	23.50	percent
Seeds,	3.70	„
Edible portion,	72.80	„

Composition of the juice from the edible portion:

Total solids,	13.20	percent
Total sugars,	9.50	„
Acids (as citric),	2.70	„

Professor Colby says in discussing these analyses that the proportion of acid is larger in these samples than the general taste demands.

Cuban Grape Fruit.

—The grape fruit which is grown in Cuba has quite a different character. Its flavor is mild, and it is almost devoid of the bitter taste which is found in the American product, and which adds greatly to its palatable properties when the consumer becomes accustomed to it.

A marmalade is made from the grape fruit similar in all respects, except the peculiar flavor given by the raw material, to that made from oranges. It is evident from its high palatable properties and its wholesomeness that grape fruit will become more and more an article of value and be consumed in large quantities throughout the country.

Guava (Psidium Guajava).

—This fruit is grown very extensively in both California and Florida, also in Cuba, where a number of varieties grow wild. The white guava is a small, round fruit, grayish-white or yellow in color, and having an average weight of 1.5 ounces. The pear-shaped fruit, the guava of Peru, is about twice the size of the white variety, but otherwise resembles it very closely. Both varieties contain large numbers of small seeds scattered throughout the yellowish-white pulp. As a rule the guava is not eaten raw, but it is a fruit from which some of the most highly prized jelly pastes and preserves are made.

Composition of the Guava.

—The guava contains, in its fresh state, an average of a little less than 80 percent of water and a little more than 20 percent of solid matter. The solid materials in guavas are quite insoluble in water, more than one-half of them not passing into solution. The chief part of the soluble constituents of guavas are the sugars, and these exist chiefly in the invert state. The total percentage of sugar in guavas in the fresh state averages about six, the protein amounts to about one percent, and the ash to a little over one-half of one percent. The value of the guava, therefore, is more condimental than nutritive, and for this reason it is seen why it is not a valuable food product eaten in the raw state.

Guava Preserves.

—A large number of preserves are made from the guava, and these products are well known and relished throughout the country. The preserves are in various forms, being chiefly pastes, marmalades, and jellies. These preparations contain the aromas and flavoring qualities of the fruit, and when pure contain no added product save sugar. They contain from 60 to 75 percent of added sugar. The preserved products of the guava are generally packed in wooden boxes, lined with paper, though some are packed in glass. The crystallized guava, the guava cream, and the pastes contain large quantities of added sugar, namely, about 80 percent. These preserves naturally have a very low acid content by reason of the quantity of sugar which has been added in their preparation. In this country often the whole fruits are preserved in sugar sirup.

Hicaco (Chrysobalanus icaco).

—The fruit of the hicaco is small and round, varying from one to three inches in diameter. The average weight of each fruit is about ¹⁄₄ oz. The skin is thin and green in color, shading to red on the side exposed to the sun. It grows on a small shrub and is sometimes called the cocoa plum. The surface is somewhat shrivelled and wrinkled, and the seed weighs almost half as much as the whole fruit. The fruit is not eaten in a fresh state, but is used for making preserves. It is sweet to the taste and has a low acid content. The composition of the fresh fruit is shown by the following table:

Composition of Edible Portion

—68.9 percent.—

Total solids,	14.29	percent
Total sugar,	5.18	„
Protein,	.46	„
Acidity,	.10	„
Ash,	.96	„

These data show that the hicaco is a fruit low in nutritive value, in so far as sugar is concerned, of a low content of protein and very slight acidity.

Hicaco Preserves.

—A sample of hicaco preserves was found to have the following composition:

Total solids,	65.07 percent
Sugar,	60.08	„
Protein,	.12	„
Ash,	.14	„
Acidity,	.05	„

The above data indicate only the change in composition which would come from adding the sugar in the process of manufacture. By reason of the low acidity of the fruit the sugar in the preserves would, theoretically, be largely cane sugar. In the case mentioned, however, one-third of the sugar was inverted. Whether this was accomplished by the action of the acid on the sugar during the process of manufacture or whether by the use of molasses instead of sugar in the preserves does not appear. More likely it is due to the latter.

Kumquat (Citrus japonica).

—The kumquat is one of the smallest of citrus fruits. It stands as one extreme of that important family of which the grape fruit or pomelo represents the other. The fruit is oval in shape, about one inch in diameter, and is one and one-half inches long. It may be regarded as a dwarf orange, and was brought into the United States from Japan, although it is a native of China. The name—kumquat—is of Chinese origin and is intended to mean “Gold Orange.” The kumquat tree, under favorable circumstances, reaches a height of 10 or 12 feet and forms a compact, symmetrical, and handsome head. The pulp of the fruit is very tender and agreeably acid and the rind is spicy, as is the case with most of the acid fruits. It is not only valued as a fruit, but the tree is also highly prized as an ornament. Its beautifully colored fruit, in contrast with its green leaves, presents a most agreeable spectacle. It is grown in the United States principally in Florida. The composition of the kumquat is practically that of the orange.

Lemons.

—The citrus fruit, next in importance to the orange, if not more important, is the lemon (Citrus limonum). This fruit is grown extensively in the United States in the same localities that produce the orange, that is, chiefly in Florida and southern California. Its method of cultivation, general treatment, time of ripening and harvesting are the same as that of the orange. Its principal difference from the orange is in its greater acidity and in certain peculiarities of its aromatic and oily substances. From the rind is produced an essential oil which, while resembling that of the orange in general character, has distinct properties which easily discriminate it from the orange product. The lemon also has a correspondingly less proportion of sugar than the orange. In 22 analyses of California lemons they were found to contain 5.26 percent of acid and only 2.33 percent of sugar. The distinct feature of the lemon, therefore, is its acidity. The principal acid present in lemons is citric acid, though other organic acids are also found. The acids are either free or in combination with a base, the principal base being potash. On account of its high acidity and low sugar content the lemon is used more as a relish and in the manufacture of acid beverages than directly as a food. There are some varieties known as sweet lemons which are eaten as oranges or used directly for food purposes, but generally the lemon is too sour and acid for consumption in this manner.

Lime.

—A species of citrus fruit which is even more acid than the lemon is known as the lime (Citrus hysrix acida).

Limes are not eaten directly as food on account of their high acidity, but their expressed juice is sold throughout the world for beverages and medicinal purposes. The lime also yields an essential oil, which is very similar in character to that derived from lemons. In fact the lime may be regarded as a very sour lemon, just as the orange may be regarded as a very sweet one.

Adulteration of Lime Juice.

—Unfortunately lime juice is offered on the market often in entirely spurious forms, that is, a mixture made up with flavoring of an acid character resembling that of the natural juice. The natural juice is also frequently adulterated by the addition of preservatives. Among these, sulfurous and salicylic acids are perhaps the most frequent. Lime juice can be perfectly preserved by sterilization, and there is no necessity for the use of preservatives therein.

In the tropics there is also found a lime of a saccharine character known as the sweet lime, but this fruit does not have a very great vogue.

Mamey Colorado.

—This is a tropical fruit which is very extensively grown in Cuba, and derives its local name from a very slight outward resemblance to the mammee (Mammea americana). These two fruits, however, have no botanical or other relation to each other, nor do they have any internal resemblance. The mamey colorado is chocolate brown in color, oval or round in shape, and its average weight is about 1.5 pounds. The skin is thick and coarse. The pulp has a yellowish color, varying to a deep scarlet, and is slightly fibrous and firm, but mealy and rather dry. It has a sweetish taste with very little acid flavor. It is eaten chiefly in the fresh state and is also stewed with sugar. The fruit usually contains but one seed, though as many as four are sometimes found. The seeds are imbedded in a soft core and are irregularly oval. The natural season is from December to August. These fruits are very largely used for making preserves.

The composition of the mamey colorado is as follows:

Composition of Edible Portion

—86.10 percent.—

Solids,	34.01	percent
Total ash,	.80	„
Acid,	.10	„
Total sugar,	22.05	„

The analysis shows that the mamey colorado is a fruit which in its edible properties and nutritive value very closely resembles the banana.

Mamey de Santo Domingo (Mammea americana).

—This is a fruit extensively used in Cuba and other tropical countries. It is of a light brown color, from three to ten inches in diameter, and weighs sometimes as much as 1¹⁄₂ pounds. The skin is thick and fibrous, the outer surface being tough and covered with small brown spots. The pulp is dark yellow in color, firm, and very juicy. It has a sweet characteristic flavor and a pleasant aromatic odor. The seeds sometimes measure three inches in diameter and cling tenaciously to the pulp. It is very commonly eaten raw and is highly esteemed for preserving purposes.

The composition of the mamey de Santo Domingo is shown in the following table:

Composition of Edible Portion

—60.70 percent.—

Solids,	14.12	percent
Total ash,	.31	„
Acids,	.42	„
Protein,	.49	„
Total sugar,	9.47	„

The above data show that this fruit is very much less sweet and very much more acid than the mamey colorado and for nutritive purposes is of much less value, but by reason of its greater acidity and higher flavoring it is more suitable for the manufacture of preserves than the fruit resembling it in external appearances and name. It is used extensively in the manufacture of preserves and marmalades which are so similar in composition as not to be distinguished from each other by their chemical analyses.

The compositions of a preserve known as mamey en almibar and a marmalade known as mermelade de mamey are shown in the following table:

	Solids.	Total Ash.	Acids.	Protein.	Total Sugars.
	Percent.	Percent.	Percent.	Percent.	Percent.
Mamey en almibar,	60.05	.154	.194	.363	57.45
Mermelade de mamey,	69.74	.149	.123	.269	62.68

Fig. 52.—Jamaica Mango Tree.—(By permission American Nut and Fruit Co.)

Mango (Magnifera indica L.).

—The mango is a fruit which is highly prized throughout the world. It is a native of southern Asia, where it has been known from earliest times. In the United States the mango is chiefly grown in Florida as a horticultural crop. The mango is a tree peculiarly sensitive to frost, and therefore does not grow as far north as oranges. Its profitable cultivation at present is confined to the extreme southern part of the Florida peninsula.

The mango is an evergreen tree. In Florida, under favorable conditions of growth, it reaches as high as 40 or 50 feet. It makes a tree of graceful appearance with a dense, dome-shaped top. The color of the mango fruit is varied; it may be red, green, or yellow, or a mixture of these colors. The tree and fruit both possess an agreeable odor, and every part of the tree, almost, can be of some economic value. The ripe fruit is a delicious dessert and is wholesome. It is often recommended for its medicinal properties. The rind and fiber, as well as the unripe fruit, are acid and full of tannin, which makes them astringent to the taste. Mangos may be eaten in the raw state, and they are also valued for making preserves, pickles, marmalades, and jelly. A very popular sauce known as mango chutney is prepared from the mango and is largely used in the United States and England, being mostly imported from India. The appearance of the tree is shown in [Fig. 52].

Oranges (Citrus aurantium).

—This fruit is characterized by its delightful flavor and by the distribution of certain aromatic oils, especially in the rind, which give it a peculiar aroma and flavor. The orange has a thick yellow rind which, while edible, is not usually eaten, but is the source of valuable essential oils. A large part of the orange, as far as weight is concerned, is not usually eaten; usually from 25 to 40 percent of the weight is in the rind or some inedible portion. The ash of the orange is usually less than one-half of one percent. The predominant organic acid of the orange is citric, although other organic acids are present. The quantity of protein present in an orange is very small, usually not exceeding very much a half of one percent. The quantity of sugar varies greatly in different samples. It is present both as cane sugar or sucrose and as reducing or invert sugar. In the very sweet orange the quantity reaches as high as 10 percent or even greater, while in the sour orange it is less. The principal food value of the orange, as far as nutriment is concerned, is its sugar. The orange, however, has other valuable properties, especially from a hygienic standpoint, aside from its nutriment. The organic salts which it contains, the organic acids, and other condimental material make the orange an exceptionally wholesome fruit, exercising a beneficial effect upon the digestive process and especially aiding in the passage of the undigested food through the alimentary canal. The orange is a fruit which has lasting keeping qualities. It is not unusual to see ripe oranges which are edible hanging on the same tree with the blossoms which are blooming for the next year’s crop. In California and Florida the oranges begin to ripen in November and may be continuously harvested until the following April, if it be advisable to leave them on the tree for that length of time. Owing to the thick and resistant skin of the orange, it can be kept for a long time without material deterioration after harvesting, if care be taken to avoid bruising or injuring the fruit in any way while handling. Oranges thus harvested and wrapped in paper and kept at a low temperature will keep for weeks and even months, and still be edible and nourishing. This property of the orange makes it possible to supply the markets of the world practically throughout the entire year with one of the most delicious and nutritious of fruits. In former years the orange was regarded as a luxury, but at the present time it is a staple article of diet even for people in moderate circumstances, and is often eaten by those who are poor. In [Fig. 53] is given a typical illustration of a California orange grove.

Fig. 53.—An Edge of a California Orange Grove.—(Bureau of Plant Industry.)

The culture of the orange has demanded the highest agricultural and scientific skill, and perhaps there is no crop produced to which greater attention has been paid. In Florida, especially, the oranges are grown on soil which is not much more than poor sand, and hence the scientific feeding of the trees, that is, the fertilization of the soil in which they grow, is necessary to success. As a result of this application of science luxuriant crops of oranges are found growing upon sandy soil which without scientific treatment would be almost barren. The soils in southern California, on the other hand, are very rich in natural plant food, but this does not obviate the necessity of scientific manuring. Oranges grow throughout the year in tropical and semi-tropical regions. It is considered by connoisseurs, however, that the oranges grown in the semi-tropical regions, that is far enough north for a little frost to come during the winter, but without a sufficient degree of cold to injure the trees, are of better quality than those grown in tropical regions where frost is unknown.

Fig. 54.—The Original Seedless Orange Tree.—(Courtesy Bureau of Plant Industry.)

The Seedless Orange.

—The variety of orange which contains no seed has been widely cultivated in the United States, and by reason of the absence of seeds is more highly prized by many than the ordinary orange for edible purposes. Since the orange tree has been cultivated by grafting rather than by direct production of the different varieties from the natural seed, it has been possible to secure a fruit without seeds. Whether such an unnatural product will continue to maintain its high rank as an edible product remains to be seen. The seedless orange tree, from which are descended the greater part of these trees in the United States, was secured by Mr. William Sanders from Bahia. Its present appearance in the greenhouse of the Department of Agriculture is shown in [Fig. 54]. The naval orange is exceedingly beautiful as it grows upon the tree. A bunch of these oranges growing on the parent tree in Washington is shown in [Fig. 55].

Fig. 55.—A Group of the Washington Navel Orange on the Tree.—(Courtesy Bureau of Plant Industry.)

Pineapple.

—The pineapple is a fruit grown very extensively in tropical and also subtropical countries. It is a crop of great importance in Florida. The flavor and aroma of the pineapple grown in subtropical countries is often preferred to that of the tropical grown fruit. Pineapples grow best when sheltered to some extent from the direct rays of the sun. In Florida it is planted near live oaks, where a partial shade is secured. It is often artificially covered by means of narrow boards placed near together and yet leaving abundant space for the sunlight. Sometimes these covered fields are two or three acres in extent. In [Fig. 56] is given a representation of the pineapple growing under a covering of this kind in Florida at the Agricultural Experiment Station, Lake City.

Formerly pineapples were regarded as great luxuries, and often were set up in the center of the table as an ornament rather than as a dessert. They have now become very common and are frequently used as a dessert, for flavoring ice cream, for preserving, and for general use as a fruit.

Fig. 56.—Covered Pineapple.—(Courtesy of Florida Experiment Station.)

Adulteration of Pineapples.

—The only adulterations which are found in pineapples are of course in the canned product. Investigations in the Bureau of Chemistry show that adulteration is not extensively practiced, unless the addition of cane sugar without notice can be so regarded.

From the point of view of the collection of duties, the addition of cane sugar without notice is an adulteration, since under provision of law pineapples canned in their own juice pay one rate of duty and when preserved with sugar pay another. Inasmuch as the label of a food product should tell the whole truth concerning it, the addition of cane sugar, without notice to that effect upon the label, is calculated to deceive and should not be practiced. There is no objection of any kind to the use of cane sugar in the canning of pineapples if the label indicates that this has been done. On the other hand there is no reason why the addition of sugar should be practiced. The pineapples are bought and consumed for their natural flavor, and not on account of the added sugar which they may contain. In the canning of pineapples it is just as easy to secure complete sterilization in their own juice as it is to secure it with the added sirup. In practice, however, it is more convenient after filling the cans with the pieces of pines to add a sugar sirup to fill up the spaces than to secure sterilization by the application of heat alone, which would not cause a sufficient quantity of juice to exude to fill up the interstices of the cans, and they, therefore, would be partially empty.

Canned Pineapples.

—There is a very large trade in this country in canned pineapples imported from Singapore and the Straits Settlements and the Bahamas. The pines are usually canned with the addition of sugar, and those that come to our ports are as a rule sweetened only with cane sugar.

A large number of analyses has been made of these canned pineapples in the Bureau of Chemistry and the general data which were secured are presented below:

Canned pineapples from Singapore, average, maximum, and minimum composition:

	Solids.	Sugar.	Protein.	Ash.	Acidity.
	Percent.	Percent.	Percent.	Percent.	Percent.
Average,	20.15	17.90	.46	.28	.30
Maximum,	25.30	25.10	.60	.36	.43
Minimum,	18.18	14.87	.39	.21	.16

The above data show that it is possible to compute the average quantity of sugar which is added in the preparation of the sample. If we assume in round numbers that the natural pine contains 12 percent of sugar, we find that approximately eight pounds per hundred of fruit have been added in the preparation of the pines from Singapore.

Below is found the average, maximum, and minimum composition of ten samples of canned pineapples from the Straits Settlements:

	Solids.	Sugar.	Protein.	Ash.	Acidity.
	Percent.	Percent.	Percent.	Percent.	Percent.
Average,	21.04	18.45	.47	.26	.26
Maximum,	24.28	21.94	.57	.32	.32
Minimum,	17.32	14.54	.39	.22	.17

These data show that the preparation of the pines in the Straits Settlements for shipment in cans is the same as that in Singapore. The average amount of sugar added appears to be about one percent greater.

Average composition of canned pineapples from the Bahamas:

	Solids.	Sugar.	Protein.	Ash.	Acidity.
	Percent.	Percent.	Percent.	Percent.	Percent.
Average,	13.78	10.69	.34	.38	.57
Maximum,	26.78	22.43	.46	.50	1.18
Minimum,	8.54	6.33	.20	.22	.22

The above data show that nearly all the canned pineapples coming from the Bahamas must be regarded as canned in their natural juice without the addition of sugar. Of the whole number of samples examined, only four gave any indication of containing added sugar.

Composition of the Pineapple.

—The average composition of twenty-two samples of fresh pineapple grown in Florida, as determined in the Bureau of Chemistry, is as follows:

Total solids,	13.85	percent
Total sugar,	11.69	„
Protein,	.40	„
Ash,	.42	„
Acidity,	.52	„

Of the sugars 4.44 percent existed in the form of invert or reducing sugar and 6.88 percent as cane sugar. These data show that the value of a pineapple as a food product lies chiefly in the sugar which it contains. The ethereal and aromatic properties of the pineapple give to it its chief value as a food, since it is the flavor and aroma rather than the nutriment in the fruit which make it valued as a food. These flavors and aromas are due to essential oils and ethers or compound ethers, and they exist in such minute quantities as to escape ordinary chemical investigation. A study of the details of analyses show that there is a wide variation in the percentage of sugar. In two instances the total sugar fell below eight percent, but those evidently were green and imperfect samples and were not included in the general average.

The highest quantity of sugar found in any case of a Florida pineapple was 15.28 percent.

The data show that in general it may be said that the Florida pineapple contains nearly 12 percent of its weight of sugar.

Average Composition of Cuban Pineapples.

—The average composition of 10 samples of Cuban pineapples examined in the Bureau of Chemistry is shown in the following data:

Total solids,	14.52	percent
Sugars,	11.87	„
Protein,	.40	„
Ash,	.35	„
Acidity,	.56	„

These data show that the Cuban pineapple is only a trifle sweeter than that grown in Florida and has in general the same composition.

The Florida pineapples when placed on the market have qualities which are by most connoisseurs judged to be superior to those of Cuban origin, although these qualities are not indicated by any marked difference in the analytical results.

The average composition of Bahama pineapples, examined in the Bureau of Chemistry, is given in the following table:

Total solids,	14.81	percent
Sugar,	12.22	„
Protein,	.48	„
Ash,	.40	„
Acidity,	.77	„

The Bahama pineapple, as is seen by the above data, is somewhat sweeter than the Florida or Cuban grown fruit and also has a higher acidity.

Average Composition of Porto Rican Pineapples.

—Two samples of Porto Rican pines, examined in the Bureau of Chemistry, had the following composition:

Total solids,	15.91	percent
Total sugar,	15.36	„
Protein,	.48	„
Ash,	.37	„
Acidity,	.72	„

The other samples of pines coming from Porto Rico were so immature that it was found they contained only about one-half the percentage of sugar and one-half the total solids of the ripened fruits. They were probably harvested in an immature state in order to withstand the vicissitudes of transportation. The above data show that the ripe pines of Porto Rico are even richer than those of the Bahamas in sugar and nutritive value.

The average, maximum, and minimum of all samples of the fresh pine from all countries examined in the Bureau of Chemistry show the following composition:

	Solids.	Sugar.	Protein.	Ash.	Acidity.
	Percent.	Percent.	Percent.	Percent.	Percent.
Average,	14.17	11.90	.42	.40	.60
Maximum,	18.86	15.28	.57	.55	.85
Minimum,	10.78	8.20	.21	.27	.30

In order that some idea might be obtained of the composition of the pines grown at Singapore and Nassau, the consuls in those localities were requested to secure the preservation of the pines by sterilization without the addition of any substance, that is, their preservation in their natural juice. In this condition the fruit of the pine, naturally preserved, was sent to the Bureau of Chemistry and subjected to analysis with the following average results:

Average Composition

(ten samples from Singapore).—

Solids,	13.39	percent
Sugars,	11.73	„
Protein,	.48	„
Ash,	.38	„
Acidity,	.39	„

Average Composition

(two samples from Nassau).—

Solids,	13.18	percent
Sugars,	10.86	„
Protein,	.40	„
Ash,	.41	„
Acidity,	.58	„

The above data show that the pineapples grown in Singapore and Nassau are not notably different in composition from those grown in Florida, Cuba, and Jamaica. All the data indicate that the pineapples grown in different parts of the world have practically the same composition at the same state of maturity.

Sapota (Sapodilla) (Sapota zapotilla (Jacq.) Coville).

—This is a tropical fruit which is grown in large quantities in Cuba, where two varieties are known, differing only in shape, one being round and the other oval. In the Havana markets the latter variety is incorrectly known as the nispero. This name, however, is properly applied to the fruit loquat (Eriobotrya japonica). The fruit is small, weighing usually under two ounces, has a brown or brownish-green color and in general appearance resembles a smooth, dark potato. The skin is thick and coarse in texture, the pulp is yellowish-brown in color, granular in texture, and rich in juice. The odor is characteristic, and the taste is quite sweet. The seeds number from one to five and are contained in a soft open core,—they are of a brownish-black color with a single white stripe. They measure from three-quarters to one inch in length. The fruit comes into use about the first of April and lasts until the end of summer. It is a very popular fruit in summer and deserves more attention in the various markets than it has yet received. The sap of the sapota tree and juice of the green fruit when concentrated furnish the material known as chicle, from which chewing-gum is made. The compositions of the round and long sapota and the natural preserved pulp of the sapota are given in the following table:

Composition of Edible Portion.—

	Edible Portion.	Composition of Edible Portion.
		Solids.	Total ash.	Acids.	Protein.	Total sugar.
	Percent.	Percent.	Percent.	Percent.	Percent.	Percent.
Round sapota,	76.40	23.07	0.384	0.132	0.350	10.85
Long sapota,	80.90	21.01	.555	.162	.650	12.76
Natural sapota preserves,	....	22.95	.399	.086	.231	11.30

The sapota is also used in the manufacture of preserves by boiling it with sugar in the usual way. The analyses show that the sapota is a fruit which is principally valuable as a carbohydrate food. It has, however, very little acid, and is a much sweeter fruit than the anona and, therefore, more pleasant to the taste.

Star-apple (Cainito) (Chrysophyllum cainito).

—The star-apple is one of the less important fruits which abound in Cuba. It is not very extensively used, but medicinal properties are attributed to it. Three different varieties are sold in the Havana markets,—one of a white color and two purple. The first attains the size of a small apple, approaching about seven ounces in weight. There are two kinds of meat in the pulp; the outer portion is a white, gelatinous matter which contains the small black seed and is really the edible portion, and constitutes about one-third the weight of the fruit. The outer fibrous and purple portion of the flesh is inedible. The inner pulp has a sweet characteristic flavor and is eaten raw. No preserves were found made of this in Cuban markets. The composition of the white star-apple is shown in the following table:

Composition of Edible Portion

—41.80 percent.—

Solids,	14.23	percent
Sugar,	7.91	„
Protein,	.67	„
Ash,	.35	„
Acidity,	.05	„

These data show that the fruit is not of a very high nutritive order, and on account of its low acidity it is not suitable for the making of preserves.

Tamarind (Tamarindus Indica).

—This fruit belongs to the leguminous family and forms a dark brown pod from one to six inches in length and from three-fourths of an inch to one inch in width. The rind is thin and very brittle. Within the pod is found a dark-colored pasty material, closely attached to the seed sacks and joined to the stem of the pod by coarse fibers. This pasty material constitutes the edible portion of the fruit and has a very sour taste which serves to mask the large amount of sugar, sometimes as much as 30 percent, which it contains. The tamarind is remarkable as having the highest content both of acid and sugar of any of the edible fruits which are in common use. It contains more acid, for instance, than the sourest lime and more sugar than the sweetest fruit. The tamarind is not very largely used directly for edible purposes but is a component of many refreshing summer beverages and is used for flavoring other products. It has mild purgative properties, and hence its intermittent use in small quantities tends to keep in proper regulation the mechanical movements which are so necessary to normal digestion.

Composition of the Tamarind.—

Water,	47.47	percent
Acid,	6.03	„
Sugar,	31.43	„
Protein,	1.36	„
Ash,	1.56	„

The above data show that the tamarind is essentially of a carbohydrate nature, its chief food value being in the sugar which it contains. On account of its high acidity very little of the sugar which is present is in the form of sucrose or cane sugar, but is mostly in an invert condition.

Preparation of Tamarinds.

—Tamarinds are not only used directly but most extensively in the form of tamarind paste which is made up chiefly by the addition of cane sugar to the pulp; as much as 75 percent of sugar is often added to the making of paste. Another form of preparation is called tamarind pulp, which has practically the same composition as the paste. These two bodies may be called tamarind preserves. The proportion of pulp to added sugar is about as 20 to 80.

Mineral Constituents of Tropical Fruits.

—The mineral content of the edible portions of fruits is important, both from a dietetic and chemical point of view.

The mineral substances in fruits not only add to their palatability but also have important functions in digestion and assimilation. The lime and phosphoric acid which the ash of fruits contain are foods that nourish certain tissues of the body, such as the bones. The other mineral ingredients of fruits take an active part in the circulation of the fluids of the body. Since the modern development of physiological chemistry, what is known as osmotic force, or the power that causes solutions to pass through membranes, is believed to be due largely to the mineral constituents of the juices of the body. These mineral constituents are therefore necessary in the food. The following table gives the total quantity of ash in the edible portion of the tropical fruits named, together with the composition of the ash in respect of its most important constituents (Bulletin 87, Bureau of Chemistry):

ANALYSES OF THE ASH OF THE EDIBLE PORTION OF THE SEVERAL FRUITS.

Description of Sample.	Total Ash.	Silica (SiO2).		Potash (K2O).	Lime (CaO).	Mag- nesia (MgO).	Ferric Oxid (Fe2O3).	Phos- phoric Acid (P2O5).	Sul- furic Acid (SO3).	Chlo- rin (Cl).
	Per- cent.	Per- cent.		Per- cent.	Per- cent.	Per- cent.	Per- cent.	Per- cent.	Per- cent.	Per- cent.
Orange (china),	0.52	1.01		40.66	10.26	5.27	1.09	8.56	2.84	2.44
Orange (rough skin),	.55	..		49.15	2.62	1.41	4.51	7.42	3.42	1.50
Orange (sour),	.57	..		45.09	7.95	2.17	2.40	8.70	2.72	.98
Grape fruit,	.39	..		44.19	7.34	3.92	1.28	11.09	3.39	1.38
Lime,	.98	..		43.01	7.84	2.36	..	8.45	2.62	4.07
Sweet lemon,	.98	..		54.35	4.29	1.08	..	9.83	4.09	1.32
Tamarind,	1.56	15.57	[34]	..	.68	2.19	..	4.99	1.40	.48
Guava,	.84	1.13		55.00	2.48	1.64	..	8.29	3.58	5.33
Banana (niño),	.70	..		46.46	.95	.42	..	10.36	2.36	6.59
Banana (oronoco),	1.08	..		52.41	1.02	1.90	..	5.16	3.32	8.48
Banana (colorado),	.83	..		51.47	.37	.65	..	3.25	2.77	7.63
Mango (French),	.53	..		47.37	6.38	1.62	..	6.49	3.67	3.88
Mango (Filipino),	.41	1.75		51.79	1.74	3.25	..	9.04	4.88	1.56
Manga,	.78	2.14		49.37	2.38	..	..	5.57	3.84	4.20
Guanabana,	.86	1.48		48.93	.44	2.17	..	9.15	4.54	3.40
Anona,	.80	.63		47.27	.81	2.07	..	13.63	3.19	3.51
Chirimoya,	1.04	..		49.73	2.21	.66	..	6.57	4.49	7.40
Sapota,	.50	..		43.13	7.49	2.83	..	2.74	4.55	17.41
Mamey (colorado),	.80	..		50.57	1.38	1.36	..	4.90	3.54	17.34
Do.,	.89	..		48.20	1.73	3.35	..	9.66	3.80	16.00
Hicaco,	.91	..		35.15	5.84	4.51	..	3.09	4.77	18.62
Cainito,	.35	..		54.75	1.31	..	..	11.00	5.50	9.46
Pineapple,	..	..		59.18	9.44	5.52	..	6.51	3.04	3.22
Do.,	..	..		57.13	4.80	3.44	..	4.29	3.65	4.08

[34] 2.88 percent sand.

The above data show that the percentage of ash in the edible portion of tropical fruits is never very high. In only three instances in the above table does it exceed one percent and in two of those only slightly. The principal mineral constituent is potash, which in round numbers may be said to constitute one-half of the total ash. Of the acid constituents phosphoric acid is the most important. In four cases the amount of phosphoric acid is greater than 10 percent of the total weight of the ash. The proportion of sulfuric acid in the ash is quite constant, while the amount of chlorin varies from less than one-half of one percent to more than 18 percent.

In this case of high ash there is a low content of phosphoric acid, which leads to the supposition that the chlorin is partially or wholly combined with sodium and potassium. In addition to the elements mentioned above the ash of edible fruits often contains notable quantities of silica and sometimes considerable quantities of sand, added accidentally or by the collection of dust. The ash of fruit also quite universally contains iron. In some cases the quantity of iron amounts to as much as four percent of the total weight of the ash. The data in the above table are calculated on the percentage of total ash and not on the percentage of pure ash, that is, ash deprived of its carbon, sand, and carbonic acid.

There are some peculiarities in the composition of the ash of tropical fruits to which attention may be called. The citrus fruits contain somewhat larger amounts of lime and iron than ordinary fruits. The ash of the tamarind contains large quantities of silica. The ash of the banana has a low content of lime and magnesia and a high content of chlorin. Attention is also called to the fact that in the ordinary combustion of an organic substance to secure the mineral matter notable quantities of the phosphoric acid and chlorin contained may be lost. Therefore, the data for phosphoric acid and for chlorin are probably lower than would be the case if all of these substances present in the fruit had been secured in the ash. The ash of pineapples is not peculiar in any respect, nor does it contain any marked amount of a constituent by which it can be identified. The pineapple, as is seen, contains slightly more potash than the other tropical fruits.