COMPONENT OF FATTY ACIDS OF BUTTERFATS, HYDROGENATED
GROUNDNUT OILS AND MUSTARD OIL
By V. R. BHALERAO, D. VENKATAPPIAH, AND C. P. ANANTAKRISHNAN, Imperial Dairy Research
Institute, Bangalore
(Received for publication on 4 November 1946)
N UMEROUS investigations have been reported on the detailed analysis of the cow butterfat,
but not much information is available about the component acids of butterfats of Indian cow,
buffalo, goat and sheep. Bhattacharya and Hilditch [1931] have studied the component acids of
buffalo butterfat, but they have not taken into consideration the presence of lower unsaturated acids
reported to be present in milk fats by Bowsworth and Brown [1933] and subsequently confirmed by
Hilditch and Paul [1936], Longenecker [1937], Hilditch and Longenecker [1938] and others. Dhingra
[1933] in his studies on the milk fats of Indian goat and sheep, has also omitted to estimate the lower
unsaturated acids. Apart from these, no data has been published of the detailed composition of the
component fatty acids of the butterfat. During some recent studies on the nutritive value of various
fats carried out at this Institute a large number of fats were collected. This opportunity was taken
to make a detailed study of the composition of buffalo, cow, goat and sheep ghee. Hydrogenated
groundnut oils of m.p. 34.1ºC., 37.0ºC., and 39.0ºC., and a sample of mustard oil were also available
and they have been analysed in detail.
EXPERIMENTAL
Samples of genuine cow ghee from different breeds namely Kangayam, Sindhi, Ongole, Gir, Sahiwal,
Hariana, Kangraj and Tharparkar were collected from different ghee-producing centres in India—
Hosur, Madras, Charrodi, Dharwar, Karnal, Hissar, Montgomery, Delhi and Bangalore. Similarly
six samples of buffalo ghee of Murrah breed from Hissar, Bangalore and Ambala, six samples of goat
ghee from Hissar, Trichur, Agra, Anand and Chikkodi, six samples of sheep ghee from Montgomery,
Anand, Sanand and Togh (Kohat) and six samples of mustard oil from Calcutta, Lahore and Cawnpore
were collected. A composite sample prepared from each class of fat was used for the detailed analysis
of the component fatty acids.
The groundnut vanaspati having m.p. 34.1ºC., 37.0ºC. and 39.0ºC, were specially prepared and
supplied for the study by the Hindustan Vanaspati Manufacturing Company, Bombay.
The method described by Smith and Dastur [1938] was adopted for the analysis of butterfats.
About 289 gm. of butterfat was esterified by refluxing for 24 hours with methyl alcohol containing
5 per cent of sulphuric acid. The bulk of the unchanged methyl alcohol was removed by distillation
and the mixed methyl esters in the residue was dissolved in ether and washed with water to remove
mineral acid. The methyl esters were then distilled through an electrically heated and packed column
similar to that described by Longenecker [1937] first under water pump and later at 2 mm. pressure
until all the esters up to C 14 or C 16 had passed over into the distillate. Butyric acid present was esti-
mated in (a) the methyl alcohol removed by distillation after the alcoholysis, (b) ether recovered from
the esters and (c) the united aqueous portions by acidifying and steam distilling. The residual esters
after preliminary fractional distillation were hydrolysed, submitted to lead salt separation and the
two groups of higher acids (solid and liquid) re-esterified and further fractionally distilled.
The composition of the various fractions were calculated according to method discussed by Irving
and Smith [1935] from the respective saponification and iodine values.
In the case of hydrogenated groundnut oil and mustard oil the initial esterification and the
fractionation of the lower esters was omitted as they are known not to contain any lower component
acids.
The general characteristics of the different fats examined are given in Table I. The percentage of
different component acids as methyl esters in the four butterfats, three hydrogenated fats and mustard
oil are shown in Tables II, III and IV respectively. These data have been summarized and expressed
as percentages of fatty acids and molar percentages in Table V.
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