الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
The data presented in this dissertation involved
studying the physical snd chemicsl propertieS beside the
chemical composition of twO varioUs types of edible fats,
namely, milk butter fats from different sources (COW,
buffalo, sheep and cow brand) and some types of hydrogenated
oils ( Primo , Hiliopolis and C.risco )’•
The obtained data deals mainly with the following
points:
1. The physical and chemical properties:
The specific gravity, refractive index and melting
point ranged between
(0.9135 to 0.9187), (1.4564 to
1.4574) and ( 34 to 35.5·C) respectiVely in various butter
fat samples and between (0.9052 to 0.9118), (1.
4664
to
1.4674) and (37.5 to 36.5·C) in different types of hydrogenated
oils •
The acid values obtained with butter -fat and hydrogenated
vegetable 011s were rether insignificant according
to the fact that the samples under investigation were rather
fresh.
The iodine values of butter fat samples ranged from
(41.6 _ 45.0) and between (99.4 to 106.1) ln hydrogenated
samples. such data indicates the presence of a high
~.aIlount.s of. un.tur,ated fatty aci~B in the hydrog
enat
ed
vegetable oils which lead to an increase in its iodine values.
The saponification values of butter fat (Cow, Buffalo~
Sheep and Cow brand) are (216.35, 217.47, 215.88 and 215.85
respectively), where for hydrogenated oils (Crisco, Primo
and Heliopoles) are (185.05, 184.21 and 184.18 respectively).
These results mean that the former contains a relative high
amounts of short chain fatty acids than the latter.
The unsaponifiable matter represents (1.1, 0.6, 0.5
and 1.46%) of cow, buffalo, sheep and cow brand butter fat
respectively, while the hydrogenated vegetable oils (Crisco,
Primo and Heliopoles) gave 0.5, 0.46 and 1.1% respectively-
The peroxide values of hydrogenated vegetable oils higher
than those of butter fat, which is probably due to the
~resence of more amount of unsaturated fatty acids leading
to more succebtability for oxidation.
The quality of butter fats and hydrogenated vegetable
oils under investigation was evaluated by determining its
peroxide value, benzidine number and thiobarbituric acid
number. The benzidine number estimated the secondary products
resulted from oxidation. Heliopoles gave the highe.t benzidine
number (17.7) with a relatively low peroxide value (13.8),
which may be due to t’-’transformation of primary oxidation
products to the secon.rv products which react with benzidine
reagent. Primo showect- high benzidine nu.ber (15.0) with
a relatively high ~roxide value (19.5). The
benzidine number ”,d perOXide value of
Crisco was relatively low (4.6 and 1.2 respectively).
The benzidine number of butter fat ranged from
(4 to
8.5) with a relatively low’ peroxide value (1.3 to 3.06).
The thiobarbeturic number (TBA) was measured at two
main maximum absorbance 530 and 450 nm. Primo and Crisco
showed the highest TBA value which indicate that the volatile
compounds as aldehydes are relatively ’h1g~ • The TBA numbers
of animal .butter fat are neglicable •
2. Chemical com osition of animal butter at and h drogenated
vegetable oils:
(a) Fatty acids composition:
Oleic acid was predominant in buffalo and cow brand
butter fat (32.35 and 36.0% respectivel~), while palmetic
acid was present in high concentration in both buffalo and
sheep butter fat (25.49 and 29.02% respectively). Stearic
was also found in both buffalo and cow brand with a high
amount (18.57 and 17.22% respectively), while myristic acid
was detected in CQW butter fat in amount 21.86%. Linoleic
acid was detected in cow, buffalo, sheep and cow brand
samples. (4.03~ 2.94, 3.75 and 2.15% respectively). Other
saturated and un$sturated fatty acids were present in all
samples with relat~ely small amounts. The major fatty
acids constituent8~f Crisco, Primo and Hellopoles were
1n both Crisco a+lf.opole.
”i:!;
Oleic acid wa. predo.lnate
respectively, while Linoleic was the main fatty acid of
Primo wi th value 33.67%. Hyd rogena ted vege table oils
contain a high amount of diene conjugated fatty acids
oWing to its high content of Linoleic acid while. tetraene
and pentaene are 1ndectable in hydrogenated vegetable
oils.
The percentage of conjugated fatty acids in cow,
bUffalo, sheep. cow brand, Crisco, Primo and He1iop01es
were 0.94414. 0.7813, 1.48743, 0.64166, 2.36619, 1.92655
and 1.8202 respectively.
The IR spectra showed th~t hydrogenated vegetable oils
contain a high amount of transisomers than animal butter
fat.
~. The unsapon1f1able matters composition:
B-Sistosterol was detected in both butter-fat and
hydrogenated oil samples with different concentrations.
Primo, Crisco and Hel10poles contain a high percentage of
a-Siatosterol (65.65, 52.73 and 6l.~ respectively), while
its a.ount in butter-fat sa.ples ranged fro. (1.08 to
6.69) 1n the unsaponifiable matters.
Campesterole -.. observed only in hydrogenated oil
.amples, Heliopole.~cent.ins the high.st a.ount (11.91).
Cholesterol waf only detected in butter-fat sa.ples
with values 90.91, ~.07, 74.78 and 3.391 in the
unsaponifiable matter of cow, bUffalo, cow brand and
sheep butter fat respectively.
The main hydrocarbon in the unsaponifiable matter
of oow, bUffalo and cow brand was C
29
(4.26, 6.84 and
9.5% respectively), while C32 is the hydrocarbon of
sheep butter fat unsaponifiables. C
24
was the main hydrocarbon
of Primo, Crisco and Heliopolis (20.62, 8.33 and
13.33% respectively).
The ratio between total sterols (TS) and total
hydrocarbon (TH) as the main constituents of the unsaponifiable
matter was calculated for different samples and can
be arranged in descending order as:
cow> bUffalo> cow brand> Heliopolis;> Primo> Crisco”’”
S~eep butter fat.