DIGESTIBILITY OF SOME NUT OILS. 3 
previous paper 1 and in amounts sufficient to supply all the subjects 
for the entire experimental period. In order to mask the presence 
of the large quantity of fat and to secure a blancmange which would 
be of uniform color and flavor for all experiments, thus avoiding 
as far as possible any psychic effects, a caramel solution was added 
to the blancmange during its preparation. 2 
The accessory foods which the diet contained in addition to the 
blancmange and which were selected because they supplied a mini- 
mum of fat, were wheat biscuit, oranges, and sugar. In case the 
subjects so desired, they were permitted to take tea or coffee, without 
milk or cream, with their meals. All constituents of the diet ex- 
cept the tea or coffee were eaten cold. 
The feces resulting from the diet under consideration were identi- 
fied by means of charcoal taken in gelatin capsules with the first 
meal of the test period and with the firs€ meal following the test 
period. The feces were collected in weighed glass containers and 
dried in an electric oven regulated to maintain a temperature of 
95° C, pulverized and analyzed. The urine was not collected or 
analyzed, and no attempt was made to maintain a nitrogen equi- 
librium, since in this investigation attention was centered on the 
digestibility of the fats. 
The customary three-clay or nine-meal test period was judged to 
be of sufficient duration to permit of satisfactory analytical results 
and still not so long as to become monotonous. No record of the 
body weights of the subjects was kept, but the men were expected 
to submit a report of their physical condition during the interdiet 
periods as well as during the experimental periods. As they re- 
ported being in normal physical condition throughout the investiga- 
tion their reports will not be referred to in detail. 
SUBJECTS. 
Men between 20 and 40 years of age, of normal health and appetite, 
served as subjects for this investigation. With one exception, they 
were all students and, while they were mainly engaged in mental 
activities, their exercise was enough to make their energy require- 
ments considerably in excess of those persons with sedentary occu- 
pations. They had all had previous experience in such experimental 
work and fully appreciated the necessity for accuracy in carrying 
out the directions given, saving uneaten portions of food, collecting 
iU. S. Dept. Agr. Bui. 310 (1915). 
2 Recently Plaisance and Monsch (Jour. Home Econ., 9 (1917), No. 4, p. 167) have 
reported that when caramel is prepared by heating sugar at temperatures of 180° C. and 
200° C. from 0.02 per cent to 0.09 per cent of furfurol is formed. The authors further 
state that if the caramel is subsequently cooked in the presence of water the furfurol is 
removed, which perhaps may explain the absence of any toxic effects resulting from the, 
use of caramel in the preparation of the blancmange. 
