614 



U. S. BTJKEAU OF FISHEEIES 



less than one-half of 1 per cent. In the present class of sea foods, 

 however, the percentage of carbohydi"ates ranges from 1 to 5.2. 

 The carbohydrates usually exist in the form of glycogen, sometimes 

 called animal starch, which is a form of sugar storage in the muscles 

 of the miollusks and crustaceans as well as in the liver of human 

 beings and mammals. The muscles that hold the parts of the shells 

 together are quite powerful, and it seems that the glycogen storage 

 takes place in these muscles. 



Table 8 — Composition of the edible portion of mollusks, crustaceans, etc. 



Name 



Fresh: 



Abalone 



Long clams 



Round clams 



Crab (eastern, hard) 



Crawfish (eastern) 



Frog's legs 



Lobster 



Mussels 



Oysters (eastern) 



Scallops , 



Shrimps 



Terrapin 



Turtle (green) 



Boiled: 



Dungeness crab (Puget Sound). _ 



Spiny lobster (southern California) 



Shrimp (Alaska) 



Preserved: 



Abalone (canned) 



Abalone (dried) 



Long clams (canned). 



Round clams (canned) 



Crab (eastern, hard, canned) 



LobFter (canned) 



Oysters (canned) ._ 



Shrimp (canned, dry pack) 



Shrimp (canned, wet pack). 



Dried shrimp 



Total 

 solids 



Per cent 

 27.2 

 20. fi 

 19.2 

 22.9 

 18.8 

 If). 3 

 20.8 

 ]5. 8 

 13.1 

 19.7 

 22.7 

 26.6 

 20.2 



22.8 

 27.4 

 30.9 



26.8 

 (>0.3 

 15.5 

 17.1 

 20.0 

 22.2 

 16.6 

 32.3 

 24.3 

 87.5 



Carbo- 

 hydrates 



Per cent 

 3.3 



2.8 

 5.2 

 1.2 

 1.0 



Fuel 



value per 



pound 



.4 



4.1 

 3.7 

 3.4 

 1.7 



3.7 

 20.9 

 2.9 

 3.0 



.5 

 3.9 



Calories 

 469 

 377 

 340 

 415 

 337 

 315 

 388 

 285 

 235 

 343 

 407 

 642 

 390 



409 

 472 

 600 



478 

 1,079 

 276 

 285 

 372 

 392 

 337 

 608 

 393 

 1,640 



Carbohydrate^'' present but undetermined. 



While it is true that the food value of mollusks and crustaceans as 

 a class is not as great on the average as that of fish flesh, still these 

 products play an important part in the diet, because they contain 

 considerable quantities of protein (essential for muscle-building 

 purposes) and are particularly noted for their delicate and imusual 

 flavors, which add variety to the diet and whet the appetite. It is 

 probably not purely by accident that in most civilized countries 

 dinners often begin with a course in which oysters, clams, crabs, or 

 lobsters figure as the appetizer.' 



Owing to the almost universal popularity of moUusks and crusta- 

 ceans people wish to eat them in seasons when they are not available 

 in the fresh state. This has led to the development of several im- 

 portant industries, such as the canning of clams, crabs, lobsters, 

 oysters, and shrimp. In Table 8 will be found some interesting data 

 on canned and dried sea foods of this type. So.me of the canned 

 products, such as oysters, shrimp, and clams, are packed in their 

 own liquor or in a light brine, and this appears to reduce their food 

 value, as a certain percentage of the nutrients dissolve in the liquid 

 during the sterilizing process. This is of no great importance, 



