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INDIAN CORN AS A FOOD FOR MAN.
L. H. MERRILL.
Among the benefits which accrued to civilized man through the discovery of the New World, the acquisition of Indian corn must be considered as one of the greatest. Its excellence seems to have quickly impressed itself upon the early settlers, and the history of the American Colonies was from the first closely identified with this grain. Since corn is not only a native of the Americas but has been cultivated by the Indians and natives of Central and South America for 20 centuries or more, it is not strange that it was found to be admirably adapted to the climate and needs of this quarter of the globe. The alacrity with which
. it was adopted by the settlers was in itself sufficient tribute to its excellence. It seems to have been the only food plant cultivated by the Indians, and so exclusively was it grown that the word corn, which formerly signified any cereal food grain, soon lost its original meaning and came to be applied exclusively to Indian corn, although the wider use of the word is still retained in England. It was a long time before this grain ceased to be the most important of our food cereals; indeed, it is scarcely a century since. wheat has assumed the leading place to which its superior bread-making qualities entitle it.
Although Indian corn now occupies the second place in importance among the cereals which in this country serve as food for man, it far exceeds wheat in the size and value of the crop produced. In 1611 the James River settlement had 30 acres of corn under cultivation. In 1621 the Massachusetts Bay colony boasted 20 acres devoted to the same crop. In 1905 there were in the United States 94,000,000 acres in corn, and the crop attained the almost incredible size of 2,707,993,540 bushels, with a value of $1,116,696,738. In the same year 47,854,079 acres were given up to wheat, and the crop was 692,979,489 bushels, worth $518,372,727. The acreage of corn was double that of wheat, and the value of the crops was in about the same proportion.
It is difficult if not impossible to grasp the full significance of such figures as these. Perhaps the imagination might be assisted by supposing the whole State of Maine one immense corn field. It would require more than 4 such fields to equal the area mentioned. If the product of this vast tract were put in bushel baskets, and these baskets could be arranged in a line upon the equator, allowing 18 inches to a bushel, the line would extend around the earth 30 times, and would furnish 30 bushels of grain to every man, woman and child in the United States.
Of course but a small fraction of this amount is utilized as human food. There are no reliable statistics to show how much is thus consumed, but it is doubtful if it exceeds one bushel in 50 of the total crop. Its use today is much more general in the South than in New England, where for the most part it is eaten only at irregular intervals as brown bread, johnny-cake, or occasionally as hominy. The colonists, following the example of the Indians, ate parched corn, either entire or in the form of a coarse meal. The virtues of this latter preparation, known as
nocake,” have been highly extolled, and it seemed to fill the high position now occupied by the predigested cereal breakfast food. Other dishes which found favor with the colonists, composed wholly or in part of corn, were hominy, hasty pudding, johnny-cake, brown bread, pone, samp and succotash, the last consisting of green corn cooked with beans. Although wheat has so largely replaced corn, it may be questioned whether we can not profitably make a fuller use of the cereal which seemed to conduce to both the physical and intellectual vigor of our forefathers.
RELATIVE COMPOSITION OF THE CEREAL GRAINS. A statement of the comparative value of our foods requires the use of certain terms which may be briefly explained here.
Protein. Under the general name protein we include a number of bodies all of which contain nitrogen and most of which belong to the class known as proteids. These bodies possess a peculiar value in that they are absolutely necessary in our foods and cannot be replaced by any other class of compounds, although they may themselves replace to a large extent the fats and carbohydrates. The fleshy part of the animal body consists largely of protein which can be formed only by the protein of the food. Hence the protein bodies are frequently spoken of as “flesh formers.” As examples of protein may be mentioned the gluten of wheat, the curd of milk, and the white of eggs.
Fats or ether extract. Nearly all our foods contain a variable amount of fats and oils. These are readily soluble in ether which is usually employed in the chemical laboratories to remove these bodies. Since the ether also dissolves other bodies which may be present in small quantities, the term "ether extract " is frequently employed as a more exact term, though the shorter term “fats ” is often used as being the more convenient. While these bodies possess great value as foods, they may be dispensed with, since the animal is able to form fats from both protein and carbohydrates. Fats are most abundant in the animal kingdom, although very few vegetable foods are entirely free from them.
Carbohydrates. These bodies are by far the most abundant in the vegetable kingdom, the amounts in our animal foods being too small to call for notice. The term includes the sugars and starches and also the woody matter of plants, or cellulose. The sugars are very readily digested as are the starches when properly cooked. The cellulose in the older plant tissues is not easily digested by man. This hardened cellulose constitutes the “ crude fiber" of the chemist. The term nitrogen-free extract is often used to denote all the carbohydrates less the crude fiber.
Heat of combustion. The protein, fats, and carbohydrates, so far as they are digested, are all oxidized or burned in the animal body with the production of heat and body energy. The protein is not fully oxidized in the body, but produces, pound for pound, as much heat and energy as the carbohydrates. The fats are the greatest heat producers, yielding weight for weight, 274 times as much energy as the protein or carbohydrates. The heat of combustion of a food material is the heat produced by its oxidation. The energy thus developed is measured by calories, a calorie being the amount of heat required to raise one kilogram of water through one degree C., or about one pounds through four degrees F.
The ash or mineral matter of a food is what remains behind after the oxidation is complete. Being already fully oxidized it can furnish no energy, although the ash constituents may be absolutely essential to the animal.
In the table below is given the average composition of the principal cereals used for food. The analyses are quoted from
. Bul. 13, Part 9. Bureau of Chemistry, U. S. Department of Agriculture. With the exception of the rice, the analyses represent American grown grains.
Average composition of cereal grains.
* Calculated. From an inspection of the table it will be seen that of the six cereals considered, corn ranks fifth in the amount of protein which it contains, carrying only about four-fifths as much protein as wheat. On the other hand, with the single exception of oats, it contains far more fat than the other cereals and two and one-half times the quantity found in wheat. It is comparatively poor in fiber and ash, but leads in the heat of combustion, a fact that is due to the large proportion of fat which it carries.
Since the cereals are purchased for the most part in the form of flours or meals, comparisons based upon the relative composition of these products would be more valuable than those just made. In most of the digestion experiments carried out at this Station, Pillsbury's Best flour and a granulated corn meal have been used. In the following table the composition of these materials is compared with that of the original corn, with hominy, and also with meal prepared by the old process, still used in some sections of the country.
Average composition of corn products used in digestion experi
ments compared with wheat flour.
The corn meal formerly found upon the market consisted merely of unbolted ground corn, the composition of which was practically identical with that of the grain from which it was prepared. Such meal was commonly sifted before it was used, the bran and other coarse particles being thus removed. While such meal may still be found upon the market, being extensively used as food for stock, that used as a food for man is generally bolted before the meal leaves the mill, the offals or bran being sold as cattle food. Since the fat or oil, so abundant in corn, is confined largely to the germ, and since the oil is peculiarly subject to changes resulting in rancidity, the presence of the germ is predjudicial to the keeping qualities of the meal. This has lead to the production of the so-called granulated corn meal, obtained by the use of roller-mills. Instead of reducing the kernel to the desired fineness by a single operation, it is first crushed by a machine known as a degerminator which so loosens the germ and hull that they may be removed before the final grinding. It is evident that the composition of the product thus obtained will differ in several very important respects from that previously described, being poorer in fat, through loss of the germ, and also poor in crude fiber or woody matter, which