DIGESTIBILITY OF SOY-BEAN AND PEANUT FLOURS. 11 
While several investigators are giving attention to the nature and 
value of the peanut proteins, as yet little information has been 
reported regarding the biologic value of these proteins. Daniels and 
Loughlin 1 have recently reported a study of two peanut meals; one 
of which was ground roasted peanuts which contained the normal 
amount of peanut oil, the second was ground press cake which con- 
tained a relatively small amount of peanut oil. Regarding the bio- 
logic value of peanut proteins the authors state— 
Rations consisting of 67.5 grams of peanut meal, supplying 18 per cent protein, 10 
crams of lard, 5 grams of butter fat, 11.4 grams of cornstarch, and 5.09 grams of suitable 
inorganic material proved satisfactory in every way. The curves of growth * * * 
[as one of the charts accompanying the paper shows] in all cases were similar to those 
generally considered to be normal. Reproduction occurred at frequent intervals and 
three generations were obtained. Good growth was secured also with a ration supply- 
ing 15 per cent protein from the peanut meal. The proteins of peanuts are comparable 
to those of the soy bean, since it has been shown that both legumes supply the essen- 
tial amino acids in sufficient amounts for normal growth and reproduction. 
In discussing the value of soy-bean flour it should also be noted that 
this material is especially valuable for food purposes since it supplies 
the water-soluble and to a limited extent the fat-soluble accessories 
essential in a complete diet. In this connection Daniels and Nichols ? 
say: 
It contains a high percentage of a physiologically good protein, a considerable 
amount of energy-yielding material in the form of fat and carbohydrate, and a fairly 
liberal supply of the fat-soluble food accessory, as well as of the water-soluble growth 
determinant. 
And Osborne and Mendel 3 state that— 
So far as we are aware the soy bean is the only seed hitherto investigated, with the 
possible exception of flax and millet, which contains both the water-soluble and [in 
limited quantity] the fat-soluble unidentified dietary essentials or vitamins. This 
fact, taken with the high physiological value of the protein, lends a unique signifi- 
cance to the use of the soy bean as food. 
Referring to the presence of the fat-soluble and water-soluble food 
accessories in peanut meal Daniels and Loughlin * say: 
That peanuts are lacking in the fat-soluble food accessory has been shown by the 
behavior of animals which were given rations containing no butter fat * * * 
Since all the animals receiving the 5 per cent butter-fat ration were normal in every 
respect, proof is furnished for the presence of a considerable amount of the water- 
soluble food accessory in the diets. When the peanuts formed 56 per cent of the ration, 
there was sufficient water-soluble B for the experimental animals. Like the soy bean, 
it needs only to have added suitable inorganic material zine some of the fat-soluble 
food accessory to make it a complete food. 
1 Jour. Biol. Chem., 32 (1918), No. 2, p. 296. 
2 Jour. Biol. Chem., 32 (1917), No. 1, p. 96. 
3 Jour. Biol. Chem., 32 (1917), No. 3, p. 376. 
4 Loc. cit. 
