COE^ OILS.. 15 
In so far as is indicated by the physical and chemical constants 
these six oils do not appear to differ to any great extent. Such 
differences as exist are not any greater than would be expected in 
several samples of normal oil. Neither do the constants of these oils 
on the whole show any considerable divergence from those reported 
by other observers. 
QUALITY OF THE OILS. 
The only practicable means of judging the quality of an oil which 
is intended for edible purposes is by its color, odor, and taste. As 
already stated, all the oils except C, which was extracted with benzol 
from wet-process oil cake, are sufficiently light in color to make them 
acceptable for edible purposes. Immediately after the oils were 
deodorized all samples were carefully tested for general odor and 
taste. To the writer there appeared to be no perceptible difference 
between oils A, B, D, and E. The remaining two, C and F, both of 
which were obtained from oil cake, were quite inferior, and C was 
the most inferior of the entire lot. In order to obtain a more criti- 
cal opinion as to the quality of these oils, small samples of each 
were submitted to two men engaged in practical oil refining and 
experienced in the judgment of edible oils. The samples were sent 
two or three weeks after they had been deodorized, which fact 
should be borne in mind when the findings of these men are con- 
sidered. Besides the six oils under discussion, a sample of com- 
mercial corn oil bought in a grocery store 4 was also submitted, desig- 
nated as oil X. The entire list was numbered and submitted without 
any information as to their source or method of preparation except 
that all were corn oils. One of the judges considered all the oils 
except C of proper color for edible purposes. As far as odor and 
taste were concerned he thought he could detect traces of solvent 
in all the oils except A and B. Since sample B was prepared by 
benzol extraction and A was an expeller oil, the " off " odor could not 
have been due to the solvent alone. He considered all but A and B 
insufficiently deodorized and believed that the peculiar flavor of all 
but A would make them unsatisfactory for edible purposes. 
The opinion of the other man was considerably different. Oil D 
was considered suitable for salad and B and E good enough for 
cooking purposes; C was declared to be exceptionally bad, and a 
peculiar flavor was detected in F and X. While none of the oils 
were considered " choice," he would rank them as follows, from 
best to poorest : D, B, E, A, F, X, C. This judgment would place 
the two solvent oils from the germs between the two expeller oils 
* This sample of oil was purchased at a store which has a rapid turnover, but the exact 
age of the sample was not known ; hence its quality as compared with the experimental 
oils must be considered with this fact in mind. 
