to the composition of the hulls or chaff. The fat or oil comes chiefly from the germ.
Composition of Hulled Oats.—Inasmuch as the chaff is always separated from the oat flour when the latter is to be used for human food, the composition of the oat in the hulled state is of greater importance to the present purpose than in the unhulled condition. The means of 179 analyses show the hulled oats to have the following compositions:
Moisture, 6.93 percent
Protein, 14.31 "
Ether extract, 8.14 "
Crude fiber, 1.38 "
Ash, 2.15 "
Starch and sugar, 67.09 "
The removal of the hulls, as is seen, and the partially dried condition of the grain in the above analysis increases the percentage of other ingredients. The protein and fat are especially large in quantity. Oatmeals may be regarded as the richest of the cereal flours, both in protein and in oil.
The Protein of Oat Kernels.—There are three principal products in the oat kernels characterized by their different degrees of solubility, namely, protein soluble in alcohol, protein soluble in dilute salt solution, and protein soluble in alkali. The protein soluble in alcohol constitutes about 1.25 percent of the whole grain, the protein soluble in dilute salt solution about 1.5 percent, and the protein soluble in alkali the remainder, viz., 11.25 percent. The protein of oats has very little agglutinating power and, therefore, oat flour is not suitable for making bread, or rather it is very little used for that purpose.
Oat Products.—As has been intimated before, the principal oat products, as far as food is concerned, are the various forms of oatmeal commonly classed as breakfast foods. These products are prepared in various forms of agglutination and physical texture but if made from genuine oats, as there is little cause for doubt, they have essentially the same composition and nutritive power. It is doubtful if there is any preparation of oatmeal any more nutritious or palatable than the plain oat grain properly cooked. The forms in which the oat products are offered to the public are perhaps more convenient for use and in some cases by reason of heating and preparation require less trouble, but otherwise they apparently have no advantage over the simple product.
The mean composition of a number of oat flour products is shown in the following table:
Moisture, 7.66 percent
Protein, 15.48 "
Ether extract, 7.46 "
Crude fiber, 1.20 "
Ash, 1.29 "
Starch and sugar, 67.61 "
