Oats contains more protein and fat than flour and meal from other cereals. Maize meal is the most closely allied to it. Starch is present in proportion of about 38 per cent. The nitrogenous portions contain 94 per cent, protein, which is thus all available for tissue-building. There is great difficulty in completely getting rid of the husk, so a good deal of cellulose is left in the meal in the form of sharp particles. Oatmeal is obtainable in coarse, medium, and fine varieties, the two latter being those in household use. To those with a delicate digestion this makes oatmeal an unsuitable food; but for constipation oatmeal is an excellent article of diet. Oatmeal is an excellent food for the growing child. This may probably be explained by the stimulating effects of the oats on the thyroid gland (see Appendix). In some subjects it heats the blood, causing rashes and gastric derangement.
If oats are simply cleaned and ground, the result is oatmeal of various degrees of fineness. Oat flour, e.g. Scott's oat flour, is the product after the branny particles are removed - this is the best form for infants and invalids. Groats, e.g. Robinson's groats, consist of oats from which the husk has been entirely removed.
Rolling oats is another method of preparation instead of grinding. Rolled oats are more easily softened by cooking; probably the great pressure between the rollers breaks clown the cell envelopes. In some of the rolled oats preparations heat is also used. This requires less cooking in the house, and sterilises the fat, so that there is no fear of the abundant fat present turning sour and altering the flavour. "Rolled oats," Quaker oats, Avenine, Provost oats, and Porrage oats are all examples of this preparation.
Oatmeal is unfitted for breadmaking, owing to the absence of gluten. It is made into oatcakes by mixing the meal with water, fat in some form (dripping or butter), and salt. Made into cakes and baked on the girdle in the form of breadstuff, it is much used in Scotland as a breakfast breadstuff, and can either be home-made or bought in tins. Oatcake is as nutritious as bread and contains a great deal higher food value.
Oatmeal needs prolonged boiling to soften the cellulose. For persons with limited digestive power oatmeal should be cooked so as to acquire a consistence which enables it to pour readily, and on cooling it should form a soft, gelatinous mass. (For making of gruel and porridge, see p. 296).
Brose is an old Scotch dish made by stirring oatmeal into boiling water. It is not a food for a delicate digestion.
A soupplateful of porridge is equivalent in protein to two slices of a large loaf 3/4 to 1 inch thick. If the bread is buttered, it would be equal in food value to a plateful of porridge and 1/2 pint of good milk.
Maize or Corn may be dried, parched, and roasted, whole, or ground into meal of various degrees of fineness. Its chemical composition shows it to contain a considerable amount of fat and protein (three globulins, one or more albuminoids, and maize fibrine, or zein) as well as starch, and it furnishes abundant energy and heat. It is very fattening both for man and the lower animals. There are innumerable varieties, but the common kinds are known as white, yellow, and red. As a fresh vegetable, sugar corn, unless eaten very young and tender, is indigestible, and canned corn is notoriously so - chiefly on account of the husk of the kernel. It may give rise to flatulency, indigestion, and diarrhoea. When maize becomes mouldy it causes a disease known as "pellagra." The chief preparations are: -
This is digestible, and like oatmeal somewhat laxative. It makes a dry, friable bread, for it contains no gluten. As compared with wheat flour, it contains more fat but is deficient in salt. It is not largely used in this country.
Cornstarch is very white and soft; contains 53 per cent. of starch; contains proportionally little nourishment. May be used instead of arrowroot.
Indian meat'is yellow, granular, and coarser than cornstarch.
Hominy, cerealine, and samp are preparations of broken or split maize of various degrees of fineness. Samp is very coarse, and can only be used when well boiled. The first two make excellent puddings.
These are made from maize by washing away the protein and fat. They contain very small quantities of nitrogen, and are therefore only agreeable forms of starch, and are generally taken with a protein and fat, such as eggs or milk.
A small variety of maize that is roasted and swells up and bursts; it is then known as popped popcorn; it is the basis of many sweetmeats.
Mush is made of well-ground Indian meal or cornmeal boiled in salted water. It mixes well with cream, and is very digestible and nutritious.
Buck-wheat or blackwheat is used in Russia, Siberia, and Brittany. The meal has less protein and more carbohydrate than flour. It is usually eaten as porridge, and can be made into griddle cakes. It is not used in this country.
Millet or Sorghum is used in Africa, Southern Europe, and in China, but not in this country; it is similar in composition to buckwheat. White sorghum is a grass or corn, and can be converted into a flour - "dhoora" - much used in India. A fine quality of alcohol may be made from it. In the United States it is grown chiefly for molasses and syrup, and sugar is made from it.
Bread made from millet or sorghum meal when warm is fairly palatable and nutritious, and is used in China. When it grows cold it darkens and crumbles.
Rye may be said to stand very close to wheat in importance as a food. It is in use in Europe, and mainly in Germany. In Germany the rye production is double that of wheat, and in Russia it is even greater.
Rye flour yields a coarse, dark, less well-raised bread than wheat, but is equally nutritious, though not so digestible; it contains less gluten than wheaten bread, and it takes less time to raise and bake it, provided the oven is hot. If properly made it is easily assimilated, and to many people its flavour is agreeable.
Rye is often combined with wheat in France, under the name meteil, and the Spaniards combine it with barley. Rye flour is poorer in protein than a wheat flour of a similar grade. It is very apt to be attacked by the fungus known as ergot, which causes the grain to swell up and become dark purple.
Rice is the poorest cereal in protein and fat, and contains 76 per cent, starch. Rice, when boiled, swells up and absorbs nearly five times its weight of water, while some of the mineral constituents are lost in the water. It should therefore be steamed, or if boiled the water it has been boiled in should be used as stock. Rice is only moderately easy of digestion, and often gives rise to flatulence; this is probably owing to the stomach not being the place to digest starch, and hence it takes a considerable time to leave the stomach.
Its poverty in protein and fat does not adapt it for an exclusive food. It is rarely taken alone, but combined with other foods like meat or legumes rich in proteins, or made into puddings with eggs or milk.
It cannot be made into bread, but rice flour is often added to wheaten flour. Rice forms the staple food of about one-third of the human race. The whole grain is called paddy, and is coloured in various shades of yellow; when this coloured skin is removed the grain is known as rice. Rice-water makes a cooling drink (p. 35).
Barley contains more salt, fat, and cellulose than wheat, but less protein and carbohydrate. The ash of barley is rich in phosphates and iron. The proteins resemble those of oats, and do not form gluten but remain soluble; thus it cannot be made into bread, but is used as barley scones and cakes and barley meal porridge.
In the preparation of barley the whole grain is ground to form barley meal. When stripped of the husk and roughly ground it is called pot barley or milled barley; when the grains are further rounded and polished it is known as pearl barley. In the form of barley broth it forms a common article of diet.