food value; of sea mussels. 
109 
Table 7. — Showing Composition of Mussels Calculated for Fresh Substance. 
[August 15, 1908.] 
Ingredients. 
White flesh 
(male). 
Red flesh 
(female). 
Average for 
white and 
red flesh. 
In flesh: 
Per cent. 
76. 62 
2. 44 
IS- 25 
1 . 98 
3 - 19 
1. 58 
Per cent. 
76. 18 
2. 46 
15 - 38 
3- 10 
2. 24 
1. 44 
Per cent. 
76. 40 
2. 45 
15-31 
2. 54 
2. 71 
i- 5 i 
95 - 64 
. 16 
• 99 
. 01 
Nitrogen 
In liquids: 
2. 86 
83- 27 
1. 63 
IO. l8 
I . 64 
1- 74 
1 . 99 
In total edible portion: 
Fat, CCh Ext. 
The above figures indicate that, for a shellfish, the mussel contains a high percentage 
of each of the four classes of food materials and that the white-fleshed individuals (males) 
differ considerably in chemical composition from the red-fleshed ones (females), the 
latter containing a much higher percentage of protein and fat but less carbohydrate. 
This difference is accounted for by the fact that the whole body of the female, during 
the spring and summer, is distended with eggs which are rich in yolk material. It is 
during this season, therefore, that the mussels are at their best as a food. 
A fair idea of the food value of the mussel may be obtained by comparing its fuel 
value with those of several standard food materials, e. g., oysters, long clams, and 
beef. Tuel value refers to the number of calories of heat equivalent to the energy 
which the body is supposed to obtain from 1 pound of a thoroughly digested food 
material. The fuel values of various food materials are calculated by using the factors 
of Rubner, which, in terms of the English system of weights, correspond to 1,860 calories 
of energy for every pound of protein or carbohydrate and 4,220 calories for each pound 
of fat. 
Table 8. — Showing Comparative Fuel Values of Mussels, Oysters, Long Clams, and Lean 
Beef. 
Food materials. 
Refuse. 
Water. 
Protein 
(NX6.25). 
Fat. 
Carbohy- 
drate. 
Ash. 
Fuel value 
per pound. 
Per cent. 
46. 69 
Per cent. 
41. 1 
83.3 
16. 1 
86. 9 
Per cent. 
Per cent. 
0. 8 
Per cent. 
0. 85 
1. 74 
• 7 
Per cent. 
Calories. 
140 
290 
45 
235 
140 
240 
785 
10. 18 
1 . 64 
. 2 
1 . 99 
• 4 
Oysters, in shell 0 
81.4 
1 . 2 
Long clams, in shell 0 
41. 9 
49 - 9 
85.8 
55-3 
5 -o 
8. 6 
.6 
1. 1 
i -5 
Beef, hind quarter as purchased 0 . . . 
16. 6 
16. 7 
11. 2 
. 8 
° From calculations of Atwater and Bryant (1906). 
