ILLUSTRATIONS.

PLATES.

Page.

PLATE I. Blends of algarroba honey and honeydew from the Hawaiian
Experiment Station____

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Fig. 4.-Mesquit.

II. Pollen grains. Fig. 1.-Alsike Clover. Fig. 2.-Red Clover.
Fig. 3.-Alfalfa.
Fig. 5.-Cat Claw. Fig.
6.-Basswood_.

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III. Pollen grains. Fig. 1.-Balsam. Fig. 2.-Opuntia. Fig. 3.—
Lemon. Fig. 4.-Aster. Fig. 5.-Ragweed. Fig. 6.-Chicory_
IV. Pollen grains. Fig. 1.-Pine. Fig. 2.-Radish. Fig. 3.-Cu-
cumber. Fig. 4. Evening Primrose. Fig. 5.-Mountain
Laurel. Fig. 6.-Timothy----

V. Pollen grains. Fig. 1.-Guava. Fig. 2.-Honeysuckle. Fig.
3. Scarlet Sage. Fig. 4. Tiger Lily. Fig. 5. Tulip-tree.
Fig. 6.-Cotton

VI. Pollen grains. Fig. 1.-Smartweed. Fig. 2.-Buckwheat. Fig.
3.-Raspberry. Fig. 4.-Tupelo. Fig. 5.-Carrot. Fig. 6.-
Persimmon. Fig. 7.—Chestnut. Fig. 8.—Eucalyptus_----

TEXT FIGURE.

FIG. 1. Distribution of honeys analyzed, showing areas of low and high average humidity

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CHEMICAL ANALYSIS AND COMPOSITION OF

AMERICAN HONEYS.

INTRODUCTION.

Miscellaneous analyses of American honeys have been published during past years in bulletins of a number of the State agricultural experiment stations, in various chemical journals, and in the several periodicals devoted to bee keeping, but up to the present time no attempts have been made toward making a systematic study of the honeys produced in the United States. Our knowledge of the general and local conditions which affect the composition of honey is exceedingly limited, and the present bulletin was begun with the hope of making a partial contribution to the information upon this subject. As the work progressed, however, it soon became evident that many more than the one hundred analyses made would be required before any conclusions, except those of a very general character, could be drawn.

The main purpose with which the work was undertaken was threefold: First, to determine the general composition of our native honeys, with particular reference to the effects of different floral nectars and of local conditions of environment. Second, to establish a general range for the variation in the composition of American honeys which would be of assistance to the food chemist in the examination of commercial samples. The recent passage of the food and drugs act and the unfortunate extent to which the adulteration of extracted honey and honey preparations has been practiced in this and foreign countries have rendered the establishment of a uniform basis of comparison exceedingly necessary. The third object was to investigate and improve, if possible, the official methods of honey analysis. In many respects, especially in deciding between abnormal and adulterated honeys, the methods of analysis usually followed are very defective, and a detailed study of the methods used in this and other countries was undertaken with the hope of improving them.

In addition to the three main lines of investigation, a number of other questions which have a bearing upon the chemistry of honey were touched upon, such as the relationship of honeydew, gums, and other plant exudations to honey and the effects of artificial feeding of bees upon the composition of the resulting product.

DEFINITION OF THE TERM “HONEY."

c

The treatment of the subject of honey chemistry will depend, necessarily, upon a proper understanding of the term "honey." According to the committee on food standards of the Association of Official Agricultural Chemists, honey is the nectar and saccharine exudations of plants gathered, modified, and stored in the comb by honeybees (Apis mellifica and Apis dorsata). According to Blythe "honey is the saccharine matter collected and stored by one particular species of bee (Apis mellifica)." According to the Vereinbarungen Nahrungs- und Genussmittel honey is the nectar obtained from flowers by worker bees, which, after modification in the honey stomach of the latter, is stored in the cells of the comb for the nourishment of the young brood. Still more precise is the definition given in the Century dictionary: "Honey is a sweet viscid fluid collected from the nectaries of flowers and elaborated for food by several kinds of insects, especially by the honeybee (Apis mellifica). Bees often fill their cells with other substances than the nectar of flowers, as molasses, honeydew, or the juices of fruits, but the product is not true honey." For practical purposes the latter definition is too narrow, for bees almost always gather variable amounts of plant exudations other than nectar.

The great difference of opinion regarding the term " honey" is brought out in the discussion by the committee for the revision of the section upon honey in the "Vereinbarungen " where it is variously defined as the product " derived by bees from plant substances " in general," from natural plant juices" only, from "the unchanged natural juices," from the "nectar or juices of living plants," etc.

SOURCES OF HONEY.

COMPOSITION OF FLORAL NECTAR, ETC.

Chemically considered, the ideal honey is a concentrated solution of invert sugar (i. e., of the sugars dextrose and levulose in equal proportions), with traces of ash, formic acid, nitrogenous bodies, dextrin, and other organic substances not sugar. This ideal type of honey, unfortunately, is the exception, since the impurities so generally introduced by bees from plant juices, honeydew, and other sources affect the composition of honey to a very marked degree. A limit, even if it be an arbitrary one, must therefore be set for the percentage of such impurities, in order that a suitable standard may be maintained for the composition of honeys sold upon the market.

U. S. Dept. Agr., Office of the Secretary, Cir. 19, p. 11.
Foods, 5th ed., 123.

1899, p. 116.

dZts. Nahr. Genussm., 1907, 14:24.

Before taking up the composition of honey itself it will be well to consider briefly the composition of floral nectar and other plant exudations and the manner in which these are modified by the bees.

A. S. Wilson has determined the amount of reducing sugar and cane sugar in various flowers with the following results:

Determination of reducing sugar and cane sugar in various flowers (Wilson).

From these results Wilson has estimated that in the case of the clover, bees would have to make 2,500,000 visits to secure 1 pound of honey. Estimates by König for various flowers show that bees would have to visit from 100,000 to 2,000,000 flowers to obtain 1 kilogram (about 2 pounds) of honey.

A. von Planta has given the following analyses of nectars from several varieties of flowers:

Analyses of nectars from various flowers (von Planta).

An analysis of the nectar of the honeysuckle quoted by Bonnier d gives water, 76 per cent; reducing sugar, 9 per cent; sucrose, 12 per cent; dextrin, ash, etc., 3 per cent.

EVAPORATION OF NECTAR.

In the modification of the nectar by the bees several changes in composition are produced. Among the most important of these is the evaporation of the nectar to a water content of about 20 per cent. This is effected in the hive by the bees exposing the nectar in thin layers to the action of a current of air produced by the fanning of their wings. This evaporation is further hastened, according to some,

a Chem. News, 1878, 38: 93.

Chem. Nahr. Genussm., 2: 995.

Zts. physiol. Chem., 1886, 10: 227.

Sources of Honey, Sci. Amer. Suppl., August 10, 1907, p. 92.