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100.00 100.00 There is great uniformity in the ash constituents of the grain of wheat when it is not subject to irregularities in ripening, and there is but slight deviation under normal variations in soil composition.
PROTEIN.-Osborne and Voorhees' recognized and investigated five proteids. Approximately they form the following per cent of the grain: A globulin, 0.65; an albumin, 0.35; a proteose, 0.30; gliadin, 4.25; and glutenin, 4.25. Gluten is composed of several nitrogenous compounds, chiefly gliadin and glutenin. Wheat bread owes its excellence to the peculiar properties of gluten, which makes it lighter and more digestible than bread made from the other cereals. The amount and quality of gluten determine the baking qualities of a flour. It is now claimed that 55 to 65 per cent of the total gluten should be in the form of gliadin. Hard wheats have a higher gluten content than soft wheats, and consequently yield better flour. Gluten generally forms from 12 to 14 per cent of the wheat grain. Dough washed with water will retain only the crude gluten. A short growing period or a season unfavorable to full maturity of the grain increases the amount of protein. The nitrogenous compounds are the most desirable part of the nourishment found in wheat, but they tend to give a yellowish tint to the bread, “against which fashion rebels,” for the “unnatural demand of the times” is for a starchy, snow white flour.
NITROGEN FREE EXTRACT.—This forms the larger portion of both grain and flour, and is composed very largely of starch, the amount of which is easily influenced by the irregularity of
Composition Influenced by Seasons and Fertilizers.—A favorable season seems to give a high weight per bushel, a large percentage of starch, and a low ash and nitrogen content. The following table gives the results of the observations of Lawes and Gilbert at Rothamsted.?
1 Amer. Chem. Jour., 15:392-471. 2 Hunt, Cereals in Amer. (1904), p. 43.
Composition as Affected by Light.—Light is essential for the formation of proteids. The following table shows the effect of differently colored glasses upon the nitrogen and albumen content of wheat."
Climate, soil and culture are also all factors that affect the chemical composition of wheat. They are treated more fully in subsequent chapters.
The Composition of Different Commercial Grades of wheat shows that the amounts of protein and ash decrease as the grade of wheat becomes higher, while the nitrogen free extract in
Differences in protein, gluten or gliadin content do not seem to be an adequate basis, however, for the commercial grading of wheat. The grading seems to be based rather on the relative yield of first quality flour. The greater the weight of the kernel and the weight per bushel, the higher is the grade of the wheat.
Historically there has been little change in the chemical composition of wheat. It seems likely that the wheat of ancient Egypt did not differ more in composition from modern wheat of the same variety than one sample of modern wheat frequently differs from another.
1 Sci. Amer., 93 (1905): 508.
IMPROVEMENT OF WHEAT.
Early Significance.—The culture of wheat has perhaps never been exclusively the subject of individual effort, but has also always been the subject of institutional essay, however vague and remote. Since the latter phase of wheat growing became scientific in the nineteenth century, it has been fraught with a significance of the widest and deepest interest. From an institutional point of view, the growers of wheat are not sufficiently differentiated from the agricultural element of society to warrant a distinctive treatment as a class proper. Only by a statement of such characteristics of the agricultural class as are apropos for a consideration of the institutional development relevant to the culture of wheat can the subject be approached.
By proverbial repute, the tillers of the soil are, comparatively speaking, independent, unprogressive, non-co-operative, and without marked tendency toward organization. Historically, they have been the last great class to be brought under a progressive regime of societal institutions. There are two main causes for this, neither one of which is inherent in the class. The first and fundamental cause is that agriculture is an occupation in nature and conditions such as to require isolation of those engaged in it, with comparatively little division of labor among them. It is an industry as broad as the land upon which it takes place, and admits of no concentration. On the other hand, taking the number of people adequately supported on a given area as a test, the industry is universally developed by a decrease in the size of the holdings of each individual, and by the diversification of labor consequent to this decrease. The second cause, more remote and less important than the first, is that in agriculture the influence of competition is necessarily indirect, and under certain conditions entirely inoperative. In civilized life competition in one form or another has always given a great impetus to organization and co-operation. In modern agriculture, especially if the farmer owns his land, the only point at which the influence of competition can enter is in the sale of farm products.
Other things being equal, a progressive farmer may be able to offer his wheat for sale at a price below the cost of production for the unprogressive grower. While this is competition, its point of incidence is mainly below the line of subsistence for the farmer, and as most farmers are above this line, much of the force of competition is lost. When a government guarantees to an individual the ownership of a certain area of land, he has a monopoly of that area as long as he raises enough produce from it to pay the taxes, or their equivalent, for the governmental guarantee, and to keep himself supplied with the necessaries of life. If he is unprogressive and isolated in his farming, he is quite free to continue so his whole life, and his son and his grandson are just as free to follow in his footsteps.
In the early days the farmer looked to better informed powers than those of human origin for the solution of difficult problems. Wily and insinuating shamans and medicine men astutely took a benevolent interest in him by unfolding, interpreting, and at times even creating, the knowledge and instruction which numerous deities dispensed through these, their agents, for the benefit of agricultural mankind. When to plow, sow, harvest, and when to sell his crop, were thus made manifest to him by the deities whose special business it was to know these things. The gifts of rain and sunshine were in their hands. They alone were the instrumentalities of fructification and bounteous harvests. With the advance of civilization, however, the deities became less communicative, the shaman's magic power waned and became less occult, while his usual recompense grew more burdensome to those who paid it, and his functions became differentiated and were gradually assumed by the botanist, the chemist, the agriculturist, the physicist, the miller, the speculator, the instructor, and above all, the experimenter. As the paternal concern of the gods and medicine men for the farmer became relaxed, little interest was taken in him for centuries, and he has never since been the object of such profound solicitude from any source. In the middle ages and during the conquests of the Goths, Vandals and other barbarians, agriculture in Europe ebbed to the lowest degree of respectability. It was revived by the Saracens of Spain, and by their successors, the Moors, it was carried to a height perhaps not surpassed in Europe before the last quarter of the nineteenth century.
While Plato, Socrates and Pliny took an interest in agriculture, it is claimed that the oldest of writers on husbandry whose works have survived is Cato, the Roman Censor (234-149 B. C.). In 1757, Home stated that Virgil and Columella were still the best authors on this subject. From the downfall of the Roman democracy until the dawn of English history, little was written on agriculture. At times it was encouraged in a general way and highly honored, as it always has been in China, but usually the farmer was left to work out his own salvation. This he did, and successfully, though it required centuries of time. He no longer relies for information upon the elucidations of subtle shamans revealing the will of elusive, evasive, and ever vanishing gods, creations of the fancy. In nearly every civilized country of the world he is supported by scientifically grounded institutions. As these are practically the scientific foundation of modern wheat raising, especially of some of its most recent and interesting phases, they are considered of sufficient importance here to be taken up briefly.
The National Governments of all of the principal wheat growing countries of the world are factors in an official capacity in the culture of wheat, and at times millions of dollars are expended by a single government in endeavoring to solve some problem of unusual importance. In the United States, Washington in 1796 suggested the establishment of a national board of agriculture. The first appropriation made by Congress for agricultural purposes was in 1839, $1,000. Lincoln approved the act which established our National Department of Agriculture in 1862. Under Cleveland, in 1889, it was raised to an Executive Department.
The development of the department has been surprising, especially in recent years. The things most characteristic of it have been its rapidly increasing magnitude, the study of questions most diversified in interests and far-reaching in impor· tance, and the thorough, effectual and scientific methods employed. As new interests arose, were investigated, and in