THE RELATIVE RATE OF ABSORPTION OF DIFFERENT OILS AND FATS
By V. R. BHALERAO, D. VENKATAPPIAH and C. P. ANANTAKRISHNAN, Imperial Dairy Research
Institute, Bangalore
(Received for publication on 16 December 1946)
T HE relative nutritive value of natural oils and fats is generally judged by the rate of a ssimilation
and the percentage of utilization in the body. With regard to the rate of absorption of
different fats, a number of investigations have been reported. Steenbock et al [1936] determined the
comparative rate of absorption of different fats in experiments with rats following the technique
of Irwin et al [1936] and indicated that in general lard and hydrogenated oils were absorbed at approx-
imately the same rate, while butter oil, halibut liver oil and codliver oil were absorbed at a more
rapid rate. Irwin et al [1936] found that hydrogenation decreased the rate of absorption of an oil, but
the variations in the melting point below body temperature were without effect. Basu and Nath
[1946] found that there existed a real difference in the rate of absorption of cow butter fat, mustard
oil, cocoanut oil, sesame oil and groundnut oil in a four hour period, but after six hours all the fats
were absorbed almost to the same extent.
The present communication deals with the rate of absorption of the fats commonly occurring in
India namely of butter fats of cow, buffalo, goat and sheep of edible oils ; sesame, groundnut ; cocoa-
nut, safflower, mustard and cotton seed, of vanaspathies from groundnut, sesame and cottonseed
oils and of the body fats from cow, buffalo, goat and sheep.
EXPERIMENTAL
The technique of Irwin et al [1936] was adopted. Adult rats from 4 to 7 months old weighing
about 200 gm. were fasted for 48 hours, during which period water was given ad libitum. With the
help of the stomach tube, 1.5 c.c. of melted fat was then delivered into the stomach. In a similar
way 1.5 c.c. of the fat was delivered into beaker and weighed. The average of three such weighings
was taken as the weight of the fat fed.
At the end of four hours after feeding the fat, rats were decapitated and the abdominal cavity
opened. The stomach, intestine and caecum were removed immediately from the body cavity.
Each section was filled with distilled water and after ten minutes the contents were emptied in a
beaker. The sections were then filled with petroleum ether (40°C.—60°C.) and after ten minutes
the contents were emptied in the same beaker, The stomach and the caecum were cut wide open
and washed thoroughly with a jet of water and petroleum ether. The intestines were stripped manually.
The contents of the beaker were exhaustively extracted with petroleum ether, the ether solution
was dehydrated and the solvent removed in a tared dish and the fat residue dried at 100°C. for three
hours and weighed.
Ten rats were used for each sample. As the sex was found not to play an important role in the
rate of absorption by Irwin et al [1936] the rats of both sexes were used.
In calculating the absorption values, the amount of fat present in the stomach after 48 hours
fasting was also taken into consideration. The rats were killed after the fasting period and the fat
extracted as before.
RESULTS
The rates of absorption together with their standard errors of the mean for different fats are
shown in Table I.
It can be observed from Table I that the rates of absorption of the milk fats form the herbivorous
animals of Indian origin range from 40.3 to 48.4 per cent in four hour period. The percentage of
absorption of cow and buffalo ghee is almost similar while goat ghee shows a slightly higher absorp-
tion. The body fats showed a significantly lower rate of absorption as compared with cow ghee.
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