164
Adding Sesame Oil to Vanaspati to distinguish it from Ghee
2. Effect adding sesame oil on the acidity develop-
ment and iodine value of hydrogenated fat.
The acid and iodine values of the samples were
determined at intervals and are shown in Tables
III and IV.
TABLE III
Iodine values of the mixtures of sesame oil and
hydrogenated fats
Description
of the sample
Brand A fat
Original reading
7 months
Brand B fat
Original reading
7 months
0 per
cent
Sesame
oil
63.99
63.97
61.37
60.51
5 per
cent
sesame
oil
65.56
65.63
61.94
61.72
10 per
cent
sesame
oil
67.24
67.19
63.71
63.82
15 per
cent
sesame
oil
69.83
69.52
65.55
65.65
20 per
cent
sesame
oil
71.10
70.54
67.04
66.84
Effect of feeding sesame cake on the
composition of secreted butterfat. It is
well known that, if oilcakes are fed in large
quantities to milch animals, the butterfat secreted
by the animals takes up some of the characteristics
of the oils. No data are, however, available on the
effect of feeding sesame cakes to cattle and the res-
ponse of the secreted milk fat to the Boudanin or
Villavecchia reaction. If animals fed on sesame
cake secrete fat that gave a positive test for sesame
oil the utility of adding sesame oil to hydrogenated
fats would be considerably diminished. To ascer-
tain this point, feeding trials were carried out with
two cows and two buffaloes. The animals were fed
sesame cake varying from 2 lb. to 10 lb. per head,
per day, over a period of ten weeks. The butter fat
was collected from individual animals twice a week
and tested for the Reichert-Meissel value, iodine
value, refractive index and Villavecchia test.
The last-named reaction was carried out by the
method given by the A. O. A. C. [1940]. The fat
used for these tests was extracted at low tempera-
ture by centrifuging the butter heated to 50° C.
At no time was it possible to get even a faint indi-
cation of the presence of sesame oil by the Villa-
vecchia reaction throughout the experimental
period. During this period the Reichert-Meissel
value, iodine value and refractive index showed
considerable change. These results therefore
showed that the compounds which give the Villa-
vecchia reaction are not secreted along with the
butterfat.
DISCUSSION
From the results of peroxide values given in
Tables I and II, it can be seen that, after an induc-
tion period of about four weeks, the peroxide values
of all the samples increased at an accelerated rate.
The results for the experimental period of seven
months showed that the addition of sesame oil did
lower the keeping quality of hydrogenated fat to
some extent after a time. When 5-10 per cent of
sesame oil was used, there was an increase in
peroxide value above the control samples, to the
extent of about 25 per cent. It must, however, be
added that considering the facts that the fats
which were dealt with were of vegetable origin
and that for these experiments the samples were
stored in glass containers, the difference in their
peroxide values cannot be considered to be objec-
tionable or excessive for all practical purposes from
the point of view of the trade. With higher con.
centrations of sesame oil than those studied, the
increase in the peroxide value was very marked.
There was hardly any difference in the iodine
and acid values of control hydrogenated fat
samples and those containing sesame oil tested
after keeping for seven months (Tables III and IV).
TABLE IV
Acid value (per cent oleic) of hydrogenated fat and sesame oil mixtures
Date
Original . . . .
After 2 months .
.
.
.
„ 4 months .
.
.
.
„ 7 months .
.
.
.
Fat
A
0.09
0.09
0.11
0.13
Sesame oil
5 per
cent
0.07
0.09
0.11
0.13
10 per
cent
0.07
0.09
0.12
0.13
15 per
cent
0.07
0.09
0.11
0.13
20 per
cent
0.07
0.09
0.11
0.13
Fat
B
0.08
0.10
0.12
0.13
Sesame oil
5 per
cent
0.07
0.11
0.11
0.13
10 per
cent
0.07
0.10
0.11
0.13
15 per
cent
0.07
0.11
0.11
0.13
20 per
cent
0.07
0.07
0.13
0.13