The nature of the nutrients is, so far as known, not different in any important respect from that of other meats. The chemical nature of the protein as shown by its products of hydrolysis has been studied in comparison with the flesh of widely different species by Osborne, whose results are tabulated farther on in this chapter (Table 32).

The light meat, such as breast, is composed of more tender fibers less firmly held together by connective tissue than is the dark meat, such as the leg muscle. Usually also the light meat contains less fat. For both these reasons it is apt to be some

what more rapidly digested, at least in the stomach, and is therefore preferable for people having weak digestion. The impression that light meat furnishes less of the substances which give rise to uric acid in the body does not seem to have been confirmed. Neither have we any evidence that the ash constituents of different meats differ in any important degree.

Game and New or Unusual Flesh Foods

Formerly game was exceedingly abundant in the United States and played a large part in the diet of the people generally. Now the amount of game is so diminished and its sale is so restricted that it has become a negligible factor in the food supply, and need not be considered here further than to point out that the flesh of game animals and game birds does not differ in nutritive value to any important degree from the meats and poultry already considered.

The same is doubtless true of most if not all of the meats which are used only occasionally in this country or are only recently coming into general use. Holmes and Deuel have recently studied the digestibility of the protein of kid, rabbit, horse, and seal meats with results essentially similar to those previously found for meats of the more familiar kinds.

Fish

The fish products of the United States constitute a food resource of growing commercial value and one which is likely to command increasing attention from consumers.

Fish to be sold "fresh" may be sent directly to market or may be kept in cold storage either chilled to ice temperature or hard frozen. Experiments begun by C. S. Smith and continued by Perlzweig and Gies indicate that fresh fish may be preserved frozen, by the best cold-storage processes, for at least two years without undergoing any important change.

The analyses made by Atwater of the commercially important kinds of fresh fish are shown in Table 28.

206

32

79.8 18.7 18.6

2 47.1 42.2 9.9 9.9

is in

moved, as purchased I 42.7 45.7 10.7 10.7 .3

.

I 28.5 54.3 15.4 15.5

3 60.0 29.9 7.4 7.4

3

.8

.6

1.5 425 1.I 304

.8 582

727

Salmon, entrails removed, as

purchased:

Shad, whole:

Edible portion

As purchased

Shad roe, as purchased

Sheepshead, edible portion

64

4 34.9 40.9 15.3 14.4

742

29.5 48.1 13.8 13.5