8 
BULLETIN 630, U. S. DEPARTMENT OF AGRICULTURE. 
black-walnut oil becomes 97.5 per cent. The protein and carbohy- 
drate portions of the diet were 61.1 per cent and 97.8 per cent digested, 
respectively, figures comparing favorably with those usually obtained 
for these constituents in other tests of this series, and indicating that 
this oil does not decrease the digestibility of other food materials 
consumed in conjunction with it. 
BRAZIL-NUT OIL. 
Brazil-nut oil is obtained from the seeds of Bertholletia excelsa, 
which is indigenous to tropical South America, and which occurs 
there in both the wild and the cultivated state. These nuts are espe- 
cially rich in oil, which, according to Lewkowitsch, 1 may make up as 
much as 73 per cent of the dried nuts. 
The oil, obtained by cold pressing a quantity of fresh Brazil nuts, 
was odorless and nearly colorless, and possessed a flavor similar to 
that of the nuts, though very much less pronounced. 
Jaffa 2 studied the digestibility of Brazil nuts when eaten as a 
part of diets containing such foods as apples, bananas, granose (a 
wheat preparation), grapes, honey, milk, olive oil, and tomatoes. In 
the three experiments an average of 106 grams of fat was eaten daily, 
with an average digestibility of 89 per cent (91.2 per cent, 84.3 per 
cent, 91.5 per cent) for the total fat, of which 92 per cent was Brazil- 
nut oil. 
The following experiments were made to determine the digestibility 
of Brazil-nut oil under conditions similar to those in the other experi- 
ments in the present series. 
Data of digestion experiments it 
ith Bra 
zil-nut oil in a 
simple 
mixed 
diet. 
Weight 
of foods. 
Constituents of foods. 
Experiment, subject, and diet. 
Water. 
Protein. Fat. 
Carbo- 
hydrates. 
Ash. 
Experiment No. 551, subject H. R. G.: 
Blancmange containing Brazil-nut oil 
Wheat biscuit 
Grams. 
1,399.0 
259.0 
874.0 
56.0 
Grams. 
657.4 
23.3 
759.5 
Grams. 
26.1 
27.5 
7.0 
Grams. 
168.9 
3.9 
1.7 
Grams. 
534.4 
200.2 
101.4 
56.0 
Grams. 
12.2 
4.1 
Fruit 
4.4 
Total food consumed 
2,588.0 
74.0 
1,440.2 
60.6 
24.3 
36.3 
174.5 
7.4 
167. 1 
892.0 
36.4 
855.6 
20.7 
Feces 
5.9 
14.8 

59.9 95.8 
95.9 
71.5 
Experiment No. 553, subject P. K.: 
Blancmange containing Brazil-nut oil 
2, 185. 
452.0 
866.0 
37.0 
• 1,026.7 
40.7 
752.6 
40.9 
47.9 
6.9 
263.7 
6.8 
1.7 
834.7 
349.4 
100.5 
37.0 
19.0 
7.2 
Fruit 
4.3 
Total food consumed 
3, 540. 
85.0 
1,820.0 
95.7 
26.1 
69.6 
272.2 
12.9 
259.3 
1,321.6 
38.8 
1.282.8 
30.5 
7.2 
23.3 
1 
Per cent utilized 

72.7 
95.3 
97.0 
76.4 
1 Chemical Technology and Analysis of Oils 
Co. (Ltd.), 1909, 4 ed., vol. 2, p. 188. 
2 Loc. cit. 
Fats, and Waxes. London : Macmillan & 
