COMPOSITION OF CHEESE AND SOME OTHER FOODS COMPARED.
In the present state of our knowledge concerning dietetics it seems best to give the housekeeper general rather than absolute rules with respect to the kind and amount of food which should be eaten at any meal or at any given time by persons in normal health living under usual conditions. It is not necessary, therefore, for the housekeeper to know the exact composition of food materials in order to cater well for her family, a rough approximation being sufficient for the purpose. In the case of cheese she will be near enough to the fact if she thinks of it as composed approximately of equal parts by weight of proteids, fats, and water. This rough conception is sufficient to associate it in her mind with the foods of high proteid value, a point which is important in connection with the making of bills of fare. It should lead her to class it also with the foods which are rich in fat and prevent her from combining it unnecessarily with other fatty foods.
In order, however, that the question of the use of cheese in the diet may be adequately discussed, knowledge of its composition in comparison with other foods is desirable, and there is an abundance of data available on this subject, since the composition of cheese and other foods has often been investigated at the Department of Agriculture, in experiment station laboratories, and in many other places where nutrition problems are studied. An extended summary of analyses of cheese of different sorts is included in an earlier publication of this department.[7]
Data regarding the composition of cheese and a few other common foods are summarized in the following table:
Average composition of cheese and some other common foods as purchased, and also on the basis of edible portion.
| Food materials. | Refuse. | Water. | Protein. | Fat. | Carbohydrates. | Ash. | Fuel value per pound. |
| Per cent. | Per cent. | Per cent. | Per cent. | Per cent. | Per cent. | Calories. | |
| Cheese | 34.2 | 25.2 | 33.7 | 2.4 | 3.8 | 1,950 | |
| Beef of average composition as purchased | 18.6 | 50.5 | 15.2 | 15.5 | .7 | 935 | |
| Edible portion | 62.2 | 18.8 | 18.8 | .9 | 1,145 | ||
| Porterhouse steak as purchased | 12.7 | 52.4 | 19.1 | 17.9 | .8 | 1,110 | |
| Edible portion | 60.0 | 21.9 | 20.4 | 1.0 | 1,270 | ||
| Loin steak, broiled, edible portion | 54.8 | 23.5 | 20.4 | 1.2 | 1,300 | ||
| Dried beef | 53.7 | 26.4 | 6.9 | 8.9 | 790 | ||
| Eggs as purchased | 11.2 | 65.5 | 13.1 | 9.3 | .9 | 635 | |
| Edible portion | 73.7 | 13.4 | 10.5 | 1.0 | 720 | ||
| Milk | 87.0 | 3.3 | 4.0 | 5.0 | .7 | 310 | |
| Bread | 35.3 | 9.2 | 1.3 | 53.1 | 1.1 | 1,215 | |
| Potatoes as purchased | 20.0 | 62.6 | 1.8 | .1 | 14.7 | .8 | 295 |
| Edible portion | 78.3 | 2.2 | .1 | 18.4 | 1.0 | 385 | |
| Apples as purchased | 25.0 | 63.6 | .3 | .3 | 10.8 | .3 | 190 |
| Edible portion | 84.6 | .4 | .5 | 14.2 | .3 | 290 |
It will be seen from the above table that cheese has nearly twice as much protein, weight for weight, as beef of average composition as purchased and that its fuel value is more than twice as great. It contains over 25 per cent more protein than the same weight of porterhouse steak as purchased, and nearly twice as much fat.
As shown by the figures in the above table, cheese contains 3.8 per cent ash. Of this a considerable part may be salt added in cheese making. Like the milk from which it is made, cheese ash is characterized chiefly by the presence of calcium (lime), magnesium, phosphorus, and iron, the average values as given in earlier bulletins of the department[8] being 1.24 per cent calcium oxid, 0.049 per cent magnesium oxid, 1.49 per cent phosphorus pentoxid, and 0.0015 per cent iron.
The total amount of the mineral matter needed per day by the body is relatively small, yet mineral matter is very important. It is commonly assumed and is probably true, that a mixed diet reasonably varied and reasonably generous will supply all the ash constituent which the body requires. If for any reason calcium and phosphorus are lacking in the diet, the amounts may be readily increased (as pointed out in one of the publications just cited) by a free use of milk and such milk products as cheese and junket, without decreasing the palatability of the diet or materially increasing its cost.