14-19-Shoib-July2011

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14 | T. Res. J. 02(01): 14-19; July, 2011
Muhammad et al., 2011
CHOLESTEROL, OMEGA-3 AND OLEIC ACID CONTENTS OF VARIOUS
OILS, BUTTER AND VEGETABLE GHEE USED AS DIETARY FATS
*1Muhammad Shoaib Akhtar, 2Darakhshan Jabbin, 1Hafiz Muhammad Irfan and
2
Naheed Abbas
1
Department of Pharmacy, University of Sargodha, Sargodha and 2Department of Rural
Home Economics, University of Agriculture, Faisalabad-Pakistan.
ABSTRACT
Cholesterol, omega-3 and oleic acid contents were determined chemically in
butter, vegetable (vanaspati) ghee and different oils routinely used as dietary
fats in this country. The data obtained have suggested that cholesterol
contents in the cooking oils were relatively much less than butter and ghee
while omega-3 and oleic acid contents were higher in the oils tested;
especially in the olive oil as compared to the ghee. Thus the use of the oils is
safe and their use should be strongly recommended as they will reduce the
risk of arteriosclerosis by lowering plasma triglyceride levels.
Keywords: Cholesterol, Omega-3, Linoleic acid, Oleic acid, Arteriosclerosis,
Dietary fats.
Corresponding Address: Prof Dr Muhammad Shoaib Akhtar, Department of
Pharmacy, University of Sargodha, Sargodha-Pakistan. Email:
[email protected]
INTRODUCTION
Cholesterol belongs to sterol group of lipids which is abundantly present in food of
animal origin like eggs, dairy products, fatty meals and animal meats (Khan,1988).
Cholesterol has been well established to perform a number of vital functions in the body,
such as providing an essential component of membranes and serving as a precursor of
bile acids, steroid hormones and vitamin D (Harvey and Champe, 1994). Blood
cholesterol level depends on several factors: sex, age, nutrition and genetic
predisposition, etc. Older people have higher cholesterol in blood which promotes the
development of various diseases including formation of gall bladder stones as well as
arteriosclerosis, leading to hypertension and angina pectoris (Colmenero, 1996).
Cholesterol balance studies in humans have indicated a wide variation in efficiency of
intestinal cholesterol absorption, ranging from 20-80%, with most individuals absorbing
between 40 to 60% of ingested cholesterol (Ros, 2000).
47-Tanzeem Manzil, Bahawalsher Raod, Mazung, Lahore, Pakistan.
Cell: 923335272042,Tel.: 924238431969, Fax: 924237117012
15 | T. Res. J. 02(01): 14-19; July, 2011
Muhammad et al., 2011
Dietary fats and oils have been reported to play an important role in human nutrition as
they supply more than twice the net energy than carbohydrates or proteins. They supply
many essential fatty acids: linolenic acid (omega-3), linoleic acid (omega-6), oleic acid
(omega-9, Botanical name: Olea europaea) and arachidonic acid, etc. in the diet. Omega3 essential fatty acids are very important because they have polyunsaturated carbon bonds
that are easily broken and do not harm the body. In addition to providing energy,
essential fatty acids are part of the structure of every cell in human body and are needed
to achieve and maintain a healthy heart but they are also essential for a healthy function
of other organs, eyes, skin, joints, hair and immune system (Schmidt et al, 1994). It has
been observed that omega-3 essential fatty acids also reduce the risk of atherosclerosis by
their lowering effect on plasma triglyceride levels (Goodnight et al, 1982). Omega-3
essential fatty acids are of different types depending upon the number of carbon atom and
number of unsaturations in which eicosapentaenoic acid (EPA) containing 20-carbon
atoms and decosahexaenoic acid (DHA) contains 22-carbon atoms. The monounsaturated
fatty acids i.e. oleic acid is found in animal and vegetable oils which is used in food
industry to make synthetic butter and cheeses and to flavor the baked goods. Cooking oil
manufacture involves cleaning the seeds, grinding them, pressing, and extrading the oil
from them. In extracting, a volatile hydrocarbon such as hexane is used as a solvent.
After extracting, the oil is refined, mixed with an alkaline substance, and washed in a
centrifuge. Further washing and refining follows, and then the oil is filtered and/or
distilled. It is then ready for packaging.(Hoffman, G 2008). Therefore, present study was
undertaken to determine levels of total cholesterol, omega-3 and oleic acid in the
common dietary fats used by local population.
MATERIALS AND METHODS
An investigation was carried out to estimate the level of cholesterol in dietary fats and
oils. For this purpose, seven samples of cooking oils, five samples of banaspati ghee,
three samples of desi ghee and three samples of butter were purchased from local market.
The samples included homemade and commercially available oils, ghee and butters
which are most commonly used here. The samples of cooking oils included Kisan
sunflower, Kisan canola oil (Pakistan Kisan Manufacturer), Planta (Dalda Foods Pvt.
Limited), Habib (Habib Cooking Oil Pakistan), Kashmir(United industries limited),
Rafhan corn oil and Olive oil. The samples of banaspati ghee included Dalda, Tullo
(Wazir Ali Industries), Kisan, Kashmir and Handi banaspati ghee. Desi ghee samples
were of Nirala, Habib and homemade desi ghee and butter samples were blue band,
homemade and desi butter purchased from a local dairy shop. For cholesterol
determination, samples of fats/oils were taken and weighed in 1g quantity. Chloroform
was used as solvents to make the volume 10 ml. Samples were stirred to dissolve
completely and diluted to 10 times. The 3ml of diluted sample solutions were taken and
absorbance was determined with spectrophotometer (Spectronic 20-D, Milton Roy
Company) after adding Liberman-Burchard reagent. The reagent reacts with the sterol to
produce a characteristic green color whose absorbance is determined on
spectrophotometer at 640 nm (Sabir et al, 2003).
47-Tanzeem Manzil, Bahawalsher Raod, Mazung, Lahore, Pakistan.
Cell: 923335272042,Tel.: 924238431969, Fax: 924237117012
16 | T. Res. J. 02(01): 14-19; July, 2011
Muhammad et al., 2011
Fatty acids composition was determined by using gas chromatography. Methyl esters
were prepared. For this purpose, approximately 200 mg (0.2g) of oil was taken in
volumetric flask. Oil sample was heated to make it moisture free. In 200 mg of oil, 25 ml
of methanol and 1-2 pellets of potassium hydroxide was added. Then contents of the flask
were refluxed for 20-25 minutes on water bath by attaching with condenser and then let it
cool for some time. Then these were extracted with hexane and two washings with water
were given, the below water was discarded and residue was taken in beaker. Sodium
sulphate (anhydrous) was added in it, shacked and was filtered off. After filtration, some
was allowed to evaporate at room temperature and the rest was saved. Fatty acid methyl
esters were prepared according to standard IUPAC Shimadzu gas chromatograph model
(7-A) fitted with a methyl lignose rate coated (film thickness=0.02µm) polar capillary
column SP™ -2330 (30m, 0.30mm) and a flame ionization detector. Oxygen free
nitrogen was used as a carrier gas at a flow rate of 5ml/min, column length is 50mm,
initial oven temperature-220◦C, injector temperature-230◦C, detector temperature-250◦C,
temperature hold (2 minutes before the run and 10 minutes after the run), volume of
sample-0.2µl, pressure-400Psi and the samples were injected with 1 µl syringe (SGE,
Australia). Fatty acid methyl esters were identified by comparing their relative and
absolute retention time to those of authentic standards of fatty acid methyl ester. A
chromatographic station (CSW32) data-handling programme did all of the evaluation and
quantification. The fatty acid composition was reported as a relative percentage of the
total peak area. The results were analyzed statistically by using standard deviation and
ANOVA (Steel and Torrie, 1984).
RESULTS AND DISCUSSION
The cholesterol level varied among different samples of cooking oils, vanaspati ghee,
desi ghee and butter. Among cooking oils, minimum concentration of cholesterol was
found in olive oil and maximum was in Habib cooking oil as shown in Table-1. The
cholesterol concentration in ghee samples ranged from 12 to 37 mg/g. Results showed
that Dalda and Tullo banaspati ghee contained lower amounts of cholesterol i.e. 12 and
13mg/g , respectively as shown in Table-1. The homemade and commercial samples of
desi ghee and butter were also subjected to cholesterol estimation. The cholesterol
contents in desi ghee were low as compared to butter as shown in Table-2.
Sabir et al, (2003) have reported that Dalda, Tullo and Habib vanaspati contained
relatively less amount of cholesterol (10, 14 and 15mg/g , respectively) and they also
observed that industrial desi ghee had more cholesterol contents. Zeljka et al, (2000) have
determined the milk fat quantity and cholesterol in butter samples originating from
village household and industry and showed that homemade butter was better than the
industrial as it contained low level of cholesterol. The present study findings have
suggested that homemade desi ghee has less amount of cholesterol as compared to
commercial products (Table-2).
47-Tanzeem Manzil, Bahawalsher Raod, Mazung, Lahore, Pakistan.
Cell: 923335272042,Tel.: 924238431969, Fax: 924237117012
17 | T. Res. J. 02(01): 14-19; July, 2011
Muhammad et al., 2011
Table-1 Concentration of Cholesterol in cooking oils and vanaspati ghees
Sr.
No.
1
2
3
4
5
6
7
Cooking Oils
Cholesterol mg/g
Mean±S.D
Banaspati ghees
3.5
4
5
4.1± 0.53
4.6 ±0.45
5.1± 0.46
5.2
Olive oil
Rafhan corn oil
Kisan canola
oil
Kisan
sunflower
Planta cooking
oil
Kashmir
cooking oil
Habib cooking
oil
Mean±S.D
Dalda
Tullo
Kisan
Cholesterol
Mg/g
12
13
25
5.7± 0.37
Kashmir
29
29.6± 0.45
6
6.5±0.49
Handi
37
37.6± 0.53
10
9.7 ±0.54
-
-
-
12
12.3± 0.32
-
-
-
12.2± 0.45
13.5± 0.54
25.4± 0.36
Table-2 Concentration of Cholesterol in Desi ghee and Butter samples
Sr.No.
Desi ghee samples
1
2
Homemade desi
ghee
Nirala desi ghee
3
Habib desi ghee
Cholesterol
mg/g
4.3
6
Mean±S.D
Butter samples
4.3 ±0.42
Homemade
butter
Blue band
butter
Desi Butter
6.5 ±0.43
7.5
Cholesterol
mg/g
5
Mean±S.D
5.5± 0.54
8
8.4± 0.32
13
13.6± 0.51
Table-3 Percentage composition of fatty acids in different cooking oils
Fatty
acids
Habib Cooking oil
(Soybean&canola)
Planta Cooking
Oil (Soybean)
Olive
oil
Kisan
Sunflower
Cooking oil
C16:0
6.24± 0.48
6.85 ± 0.49
-
6.03 ±0.46
Kashmir
Cooking oil
(Soybean
&Canola)
15.25± 0.54
C18:0
3.20 ±0.37
3.67 ± 0.39
3.77 ±0.39
18.09± 0.57
C18:1
42.65± 0.77
47.40 ± 0.81
54.32 ±0.96
17.19± 0.53
C18:2
24.50 ±0.65
27.04± 0.67
21.52± 0.62
13.03± 0.51
C20:0
-
7.87 ± 0.50
1.84 ±0.26
9.65 ±0.52
C18:3
9.55 ±0.50
7.12 ± 0.49
12.47 ±0.53
27.58 ±0.69
C20:1
C22:0
2.65± 0.35
10.40± 0.52
-
4.84
±0.47
53.94
±0.94
25.14
±0.64
5.76
±0.49
10.29
±0.52
-
-
-
Rafhan
Corn oil
11.81
±0.51
15.74
±0.52
11.84
±0.51
22.49
±0.64
29.99
±0.69
15.77
±0.53
-
Fatty acid analysis of cooking oils confirmed the presence of palmitic, stearic, oleic,
linoleic, linolenic, eicosenoic, lignoceric and erucic acids. The retention time of different
peaks of selected samples were then compared to the retention times of standard peaks
which indicated the presence of fatty acids. The results showed that their percentages as
follows: C16:0 in Rafhan Corn oil, C18:0 in Kisan sunflower cooking oil and C18:3 in
Planta cooking oil. These values correlated with Meydani et al. (1991) who have reported
47-Tanzeem Manzil, Bahawalsher Raod, Mazung, Lahore, Pakistan.
Cell: 923335272042,Tel.: 924238431969, Fax: 924237117012
18 | T. Res. J. 02(01): 14-19; July, 2011
Muhammad et al., 2011
fatty acid contents of soybean, sunflower, corn and canola oils as C16:0 10.9%, 6.02%,
11.4%, 4.1%; C18:0 4.0%, 4.7%, 1.9%, 2.1%; C18:1 (n-9) 24.2%, 20.5%, 25.4%, 56.7%;
C18 (n-6) 54.1%, 69.0%, 60.9%, 26.8%; C18:3 (N-3) 7.2%, 0.1%, 0.7% and 10.3%,
respectively. These findings have indicated that only Habib, Kisan, Kashmir, olive oil and
Rafhan cooking oils contained Omega-3 fatty acids as shown in Table-3. The percentage of
oleic acid C18:0 was 4.48% in olive oil which matched with the value 5.0% as reported by
Giuliana et al. (1994).
Vanaspati ghee is produced after hydrogenation of oils like cotton seed, canola, soybean or
palm oils in the presence of a catalyst. The contents of C18:1 was found to be 30.3% that
was in accordance with the value of 29.3% as reported by Wilson (1991) and 29.8% by
Meydani (1991). Dalda banaspati had significantly higher amount of C16:0 than Kisan
banaspati and the percentage of C18:0 was higher than the other studied banaspati ghee as
shown in Table-4.
Table-4 Percentage composition of fatty acids in ghee samples
Fatty acids Dalda
Tullo
Kisan
Handi
vanaspati
vanaspati
vanaspati
vanaspati
ghee
ghee
ghee
ghee
C14:0
1.04± 0.25
1.74 ±0.29
C16:0
20.77 ±0.62
37.28± 0.74
17.18 ±0.57
29.48 ±0.69
C18:0
16.37± 0.44
8.71 ± 0.40
-
10.68 ±0.53
C18:1 cis
25.82 ±0.67
37.28± 0.74
46.33 ±0.80
-
C18:1trans
C18:2cis
C18:2trans
C20:0
C18:3
4.48± 0.39
14.08 ±0.42
3.91± 0.38
4.63± 0.32
16.95± 0.45
12.74 ± 0.54
1.10± 0.28
1.97± 0.30
36.48 ±0.73
-
34.74 ±0.70
14.34 ±0.43
4.13 ±0.30
4.85 ±0.33
Nirala
desi ghee
2.36± 0.37
20.48±
0.60
10.40±
0.52
25.21±
0.67
5.51 ±0.41
1.02 ±0.22
It is conceivable; therefore, from the above data that the cooking oils tested contain much
less cholesterol as compared to ghees. In addition, they have been observed to possess
significant amounts of omega-3 and oleic acids. Thus their consumption by the human
beings would be safe and even lower the risk of arteriosclerosis.
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47-Tanzeem Manzil, Bahawalsher Raod, Mazung, Lahore, Pakistan.
Cell: 923335272042,Tel.: 924238431969, Fax: 924237117012
19 | T. Res. J. 02(01): 14-19; July, 2011
Muhammad et al., 2011
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47-Tanzeem Manzil, Bahawalsher Raod, Mazung, Lahore, Pakistan.
Cell: 923335272042,Tel.: 924238431969, Fax: 924237117012
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