Composition of the Food Materials.—One who intelligently provides the daily bill of fare must have some knowledge of the nature and quantity of the nutrients[pg 125] present in the different materials used as food. This information is supplied by the chemist, who has made extensive analyses for this purpose. Results of such analyses are shown in Table 1 (page 126), which gives the percentage of proteids, fats, carbohydrates, water, and mineral salts in the edible portions of the more common of our foods.
Fig. 61—Relative proportions of different nutrients in well-known foods.
Food Supply to the Table.—The main problem in supplying the daily bill of fare is that of securing through the different food materials the requisite amounts of proteids, carbohydrates, and fats. In this matter a table showing the composition of foods can be used to great advantage. Consulting the table on page 126, it is seen that large per cents of proteids are supplied by lean meat, eggs, cheese, beans, peas, peanuts, and oatmeal, while fat is in excess in fat meat, butter, and nuts (Fig. 61). Carbohydrates are supplied in abundance by potatoes, rice, corn, sugar, and molasses. The different cereals also contain a large percentage of carbohydrates in the form of starch.
| TABLE I. The Composition ofFood Materials[54] | |||||||
|---|---|---|---|---|---|---|---|
| Food Materials | Water | Solids | Proteid | Fat | Carbohydrates | Mineral Matter | Heat Value of One Pound |
| Animal foods, edible portion | Per cent | Per cent | Per cent | Per cent | Per cent | Per cent | Calories[55] |
| Beef: Shoulder | 63.9 | 36.1 | 19.5 | 15.6 | ... | 1 | 1020 |
| Rib | 48.1 | 51.9 | 15.4 | 35.6 | ... | .9 | 1790 |
| Sirloin | 60 | 40 | 18.5 | 20.5 | ... | 1 | 1210 |
| Round | 68.2 | 31.8 | 20.5 | 10.1 | ... | 1.2 | 805 |
| Veal: Shoulder | 68.8 | 31.2 | 20.2 | 9.8 | ... | ... | 790 |
| Mutton: Leg | 61.8 | 38.2 | 18.3 | 19 | ... | .9 | 1140 |
| Loin | 49.3 | 50.7 | 15 | 35 | ... | .7 | 1755 |
| Pork: Shoulder | 50.3 | 49.7 | 16 | 32.8 | ... | .9 | 1680 |
| Ham, salted, smoked | 41.5 | 58.5 | 16.7 | 39.1 | ... | 2.7 | 1960 |
| Fat, salted | 12.1 | 87.9 | .9 | 82.8 | ... | 4.2 | 3510 |
| Sausage: Pork | 41.5 | 58.8 | 13.8 | 42.8 | ... | 2.2 | 2065 |
| Bologna | 62.4 | 37.6 | 18.8 | 42.8 | ... | 3 | 1015 |
| Chicken | 72.2 | 27.8 | 24.4 | 1 | ... | 1.4 | 540 |
| Eggs | 73.8 | 26.2 | 14.9 | 10.5 | ... | .8 | 721 |
| Milk | 87 | 13 | 3.6 | 4 | 4.7 | .7 | 325 |
| Butter | 10.5 | 89 | .6 | 85 | .5 | .3 | 3515 |
| Cheese: Full cream | 30.2 | 69.8 | 28.3 | 35.5 | 1.8 | 4.2 | 2070 |
| Skim milk | 41.3 | 58.7 | 38.4 | 6.8 | 6.9 | 4.6 | 1165 |
| Fish: Codfish | 82.6 | 17.4 | 15.8 | .5 | ... | 1.2 | 310 |
| Salmon | 63.6 | 36.4 | 21.6 | 13.4 | ... | 1.4 | 965 |
| Oysters | 87.1 | 12.9 | 6 | 1.2 | 3.7 | 2 | 230 |
| Vegetable foods | |||||||
| Wheat flour | 12.5 | 87.5 | 11 | 1.1 | 74.9 | .5 | 1645 |
| Graham flour (wheat) | 13.1 | 86.9 | 11.7 | 1.7 | 71.7 | 1.8 | 1635 |
| Rye flour | 13.1 | 86.9 | 6.7 | .8 | 78.7 | .7 | 1625 |
| Buckwheat flour | 14.6 | 85.4 | 6.9 | 1.4 | 76.1 | 1 | 1605 |
| Oatmeal | 7.6 | 92.4 | 15.1 | 7.1 | 68.2 | 2 | 1850 |
| Cornmeal | 15 | 85 | 9.2 | 3.8 | 70.6 | 1.4 | 1645 |
| Rice | 12.4 | 87.6 | 7.4 | .4 | 79.4 | .4 | 1630 |
| Peas | 12.3 | 87.7 | 26.7 | 1.7 | 56.4 | 2.9 | 1565 |
| Beans | 12.6 | 87.4 | 23.1 | 2 | 59.2 | 3.1 | 1615 |
| Potatoes | 78.9 | 21.1 | 2.1 | .1 | 17.9 | 1 | 375 |
| Tomatoes | 95.3 | 4.7 | .8 | .4 | 3.2 | .3 | 80 |
| Apples | 83.2 | 16.8 | .2 | .4 | 15.9 | .3 | 315 |
| Sugar, granulated | 2 | 98 | ... | ... | 97.8 | .3 | 1820 |
| White bread (wheat) | 32.3 | 67.7 | 8.2 | 1.7 | 56.3 | .0 | 1280 |
| Peanuts | 9.2 | 90.8 | 25.8 | 24.4 | 38.6 | 2 | 2560 |
| Almonds | 4.8 | 95.2 | 21 | 17.3 | 54.9 | 2 | 3030 |
| Walnuts (English) | 2.5 | 97.5 | 16.6 | 16.1 | 63.4 | 1.4 | 3285 |
[pg 128]Variety in the selection of foods for the table is an essential feature, but this should not increase either the work or the expense of supplying the meals. Each single meal can, and should, be simple in itself and, at the same time, differ sufficiently from the meal preceding and the one following to give the necessary variety in the course of the day. The bill of fare should, of course, include fruits (for their tonic effects) and very small amounts perhaps of substances which stimulate the appetite, such as pepper, mustard, etc., known as condiments.
Purity of Food.—The fact that many of the food substances are perishable makes it possible for them to be eaten in a slightly decayed condition. Such substances are decidedly unwholesome (some containing poisons) and should be promptly rejected. Not only do fresh meats, fruits, and vegetables need careful inspection, but canned and preserved goods as well. If canned foods are imperfectly sealed or if not thoroughly cooked in the canning process, they decay and the acids which they generate act on the metals lining the cans, forming poisonous compounds. The contents of "tin" cans should for this reason be transferred to other vessels as soon as opened.
Foods are also rendered impure or weakened through adulteration, the watering of milk being a familiar example. The manufacture of jellies, preserves, sirups, and various kinds of pickles and condiments has perhaps afforded the largest field for adulterations, although it is possible to adulterate nearly all of the leading articles of food. A long step in the prevention of food and drug adulteration was taken in this country by the passage of the Pure Food Law. By forcing manufacturers of foods and medicines to state on printed labels the composition of their products, this law has made it possible for the consumer to know what he is purchasing and putting into his body.
Alcohol not a Food.—Many people in this and other countries drink in different beverages, such as whisky, beer, wine, etc., a varying amount of alcohol. This substance has a temporary stimulating or exciting effect, and the claim has been made that it serves as a food. Recently[pg 129] it has been shown that alcohol when introduced into the body in small quantities and in a greatly diluted form, is nearly all oxidized, yielding energy as does fat or sugar. If no harmful effects attended the use of alcohol, it might on this account be classed as a food. But alcohol is known to be harmful to the body. When used in large quantities, it injures nearly all of the tissues, and when taken habitually, even in small doses, it leads to the formation of the alcohol habit which is now recognized and treated as a disease. This and other facts show that alcohol is not adapted to the body plan of taking on and using new material (Chapter XI), and no substance lacking in this respect can properly be classed as a food.[56] Instead of classing alcohol as a food, it should be placed in that long list of substances which are introduced into the body for special purposes and which are known by the general name of
Drugs.—Drugs act strongly upon the body and tend to bring about unusual and unnatural results. Their use should in no way be confused with that of foods. If taken in health, they tend to disturb the physiological balance of the body by unduly increasing or diminishing the action of the different organs. In disease where this balance is already disturbed, they may be administered for their counteractive effects, but always under the advice and direction of a physician. Knowing the nature of the disturbance which the drug produces, the physician can administer it to advantage, should the body be out of physiological[pg 130] balance, or diseased. Not only are drugs of no value in health, but their use is liable to do much harm.