Page:Popular Science Monthly Volume 83.djvu/356

352 been constructed on the basis of about 13 per cent, protein calories, to be on the safe side.

It would be most desirable, therefore, if the label on packages of manufactured foods were required to give also the content of protein in addition to the total energy value. This might be done in the case of oatmeal as follows: "This parcel is guaranteed to contain 2,000 calories of heat-value, of which 14 per cent, is in the form of protein," or, in the case of milk, "700 total calories, 16 per cent, protein calories." Naturally the milk would not yield 700 calories to the bottle unless it were high in cream. The relation of total calories to protein calories might also be expressed in the form of a ratio.

A law requiring the correct labeling of foods with reference to the energy content and protein content should result in a wholesome competition among producers and manufacturers to improve the actual food value and therefore their real economic value. At present the competition runs along the line of the appearance of food and mere flavor, which, although desirable, are not the most necessary qualities to be considered in the provisioning of our people. Coal and other forms of fuel for our boilers and automobiles we must take as we find them in the earth. The only way in which we can improve their quality is by refinement, which costs nearly as much as we gain. But in the matter of fuels for our bodies there are immense possibilities of improvement without increasing the cost a particle. The fuel value of a food crop depends upon the power of the plant to utilize primarily the carbon dioxide of the air and the water of the soil in the formation of sugars, starches and oils. Under the stimulus of the sunlight the energy-of the sun is stored up in roots, grains, etc., and is not lost until the food is burned in the animal body. So long as air and water and sunlight cost nothing an improved variety of corn or wheat or oats or rice which would yield more energy should be produced as cheaply as those we are now living upon, except for the extra thought and work of selection which might be involved. But the stimulus to produce more for the money for the sake of larger sales is exactly the sort of stimulus we want the food manufacturer to have.

A standard of purity in this sense ought to have the effect also of emphasizing the expensiveness of animal food as a source of energy as compared with vegetable food. For when the corn grown in one field is fed to an ox in another the ox dissipates fully nine tenths of the energy walking about the field and stores in his body for our use as food only the other one tenth. Hence to get our full energy requirement in the form of beef even the cheapest cuts would cost us at least ten times as much as it would if we ate the corn meal. This is assuming that the cost of preparing the two kinds of food for the market, and finally for the table, is the same. The illustration is used only for