ly cooked and
then dried. Those costing 7 cents or more per pound do not contain any
greater amount of nutritive substance than those purchased in bulk at
about half the price. At one time it was believed that oats contained a
special alkaloid having a stimulating effect when fed to animals. Recent
investigations, however, show that there is no alkaloidal material in
oats, and whatever stimulating effect they may have results from the
nutrients they contain. Occasionally there is an appreciable amount of
cellulose, or fiber, left in the oat preparations, due to imperfect
milling. This noticeably lowers the digestibility. Oatmeal requires much
longer and more thorough cooking than many other cereals, and it is
frequently used as food when not well prepared. Digestion experiments
show that when oatmeal is cooked for four hours or more, it is more
readily acted upon by the diastase ferment and digested in a shorter
time than oatmeal cooked only a half hour.[5] Oatmeal is one of the
cheapest sources from which protein is obtained, and when well cooked it
can advantageously form an essential part of the ration. Unless
thoroughly cooked, the oat preparations do not appear to be quite so
completely or easily digested as some of the other cereals.

[Illustration: FIG. 32.--OAT STARCH GRANULES.]

[Illustration: FIG. 33.--WHEAT STARCH GRAINS.]

146. Wheat Preparations differ in chemical composition more than those
from oats or corn, because wheat is prepared in a greater variety of
ways. They are made either from the entire kernel, including the bran
and germ, or from special parts, as the granular middlings, as in the
case of some of the breakfast foods, and a few are made into a dough and
baked, then dried and toasted. Some special flours are advertised as
composed largely of gluten, but only those that have been prepared by
washing out the starch are entitled to be classed as gluten flours.[58]
For the food of persons suffering from diabetes mellitus physicians
advise the use of flour low in starch, and this can be made by washing
and thus removing a portion of the starch from wheat flour, as directed
in Experiment No. 30. The glutinous residue is then used for preparing
articles of food. Analyses of some of the so-called gluten flours show
that they contain no more gluten than ordinary flour, particularly the
low grades. A number of wheat breakfast foods are prepared by
sterilizing the flour middlings obtained after removal