Variety In Diet

Fish, beside being an economical source of nitrogenous substances, has much value in satisfying the demand for variety in food. Any lack in nutrients is frequently supplied by the sauces with which it is served, and by the fat used if it is fried. It would seem to be an error from the standpoint of food values to serve a rich sauce with a fish like salmon that already contains a high proportion of proteid and a large amount of fat, but an egg sauce served with a light fish like cod or haddock has its justification, not only in the additional flavor imparted, but in the additional food value.

Shell Fish

Oysters may be taken as a good type of the various shell fish that we use. The analysis of oysters shows a composition somewhat similar to that of milk, although they are higher in nitrogen and lower in fat than milk.

Average Composition Of Oysters. (Langworthy.)

(Exclusive of liquid).

Water.............................................88.3

Nitrogenous substances......................... 6.1

Fat................................................ 1.4

Carbohydrates................................... 3.3

Salts.............................................. 1.9

Comparative Cost

When milk is seven cents a quart and oysters are twenty-five, the amount of food material purchased for a given amount differs greatly in the two. When oysters are fifty cents a quart they must be distinctly regarded as a luxury, used for the purpose of providing variety, and not as a valuable source of food. Oysters are one of the few animal foods that contain a large amount of carbohydrates. These are present in the liver of the oyster in the form of glycogen.

Digestibility

The oyster is especially easy of digestion, but this digestibility is lessened by cooking. This is particularly true when the oyster is overcooked. An objecttion to the use of the raw oyster is that during the so-called fattening of the oyster, that is done in shallow water, it may become contaminated with typhoid germs derived from sewage. Some noted epidemics have been traced to this source. This simply means that greater care should be taken in the supervision of such a food supply in order that it may be protected from such possible contamination.

Clams Lobsters

Of other shell fish commonly used, clams have a similar composition to that of oysters, but contain a tougher muscle, while lobsters and crabs are generally considered somewhat indigestible because of the firmness and compactness of their fibre. The difficulty here seems partially at least to be the failure to properly masticate the flesh, as is true in so many other cases, and also the difficulty of obtaining the food in an absolutely fresh condition.

Dried And Smoked Fish

Dried and smoked fish deserve a place in the diet for the sake of variety, and because, since the water has been eliminated, a large amount of food material is obtained for a small amount of money. The use of certain varieties of canned fish has become general. Salmon is perhaps the most satisfactory of these. Special care should be taken in using canned fish to remove it immediately from the can after it is opened, and to use it within a short time. Fish that has been frozen should be cooked immediately after thawing, since it decomposes much more rapidly than fish which has not been frozen.

Cooking

Fish, particularly some varieties, such as cod, occasionally contains parasites, but these are destroyed by thorough cooking. It is essential that all fish used should be thoroughly cooked, although this does not mean that it should be cooked at a high temperature. A temperature of from 180 to 200 degrees Fahrenheit continued long enough to coagulate the proteid and render the fish opaque instead of clear, gives far more satisfactory results than boiling.

As in other cooking of flesh, this principle is apparently violated when fish is cooked in a hot oven, or fried, but as a matter of fact, the violation is only true so far as the ouiside layers are concerned, and this sacrifice is made in order to keep the shape of the fish and to develop the flavor.

Comparative Costs Of Protein And Energy As Furnished By A Number Of Food Materials At Certain Prices

From Fish as Food.