A Comparative Study on the Physicochemical Parameters and Trace Elements in Raw Milk Samples Collected from Misurata- Libya

Abstract

This research work was carried out to compare the physicochemical parameters of milk samples
from four different animal species namely cow, goat, camel and sheep. Milk samples were
collected from different areas of Misurata, Libya and analyzed for the key physiochemical
parameters, pH, titratable acidity, total solids, ash, fat, protein and lactose. Furthermore in
this study the concentrations of Zinc (Zn), Cadmium (Cd), Chromium (Cr), Magnesium (Mg),
Manganese (Mn), Potassium (K), Calcium (Ca) Copper (Cu), Iron (Fe) and Lead (Pb) in similar
commercial milk specimens from the same area were determined using microwave plasmaatomic
emission spectrometry In fresh cow’s milk, the mean concentrations of Pb, Cd, Cr, Cu,
Fe, Zn, Mg, Mn, Ca and K were 0.13� 0.19 (mg/l), 0.004� 0.001 (mg/l), 0.04� 0.01 (mg/l),
0.17� 0.11 (mg/l), 0.72� 0.02 (mg/l), 1.98� 0.04 (mg/l), 214.00� 0.20 (mg/l), 0.080� 0.05
(mg/l), 423.0� 3.5 (mg/l) and 427.0� 2.5 (mg/l), respectively. While the mean concentration of
Pb, Cd, Cr, Cu, Fe, Zn, Mg, Mn, Ca and K, in the goat’s milk were 0.761 � 0.78 (mg/l), 0.085
� 0.02 (mg/l), 1.253 � 0.18 (mg/l), 0.400� 0.08 (mg/l), 1.23� 0.21 (mg/l), 3.110� 0.15 (mg/l),
140.0� 0.31 (mg/l), 0.097� 0.07 (mg/l), 473� 5.12 (mg/l) and 510� 6.05 (mg/l), respectively.
The concentration of Pb, Cd, Cr, Cu, Fe, Zn, Mg, Mn, Ca and K, in the camel’s milk were 0.025 �
0.019 (mg/l), 0.091� 0.05 (mg/l), 0.069� 0.07 (mg/l), 0.080 � 0.05 (mg/l), 1.680 � 0.43 (mg/l),
5.380 � 1.17 (mg/l), 120.0 � 0.11 (mg/l), 0.094 � 0.04 (mg/l), 520.0 � 0.32 (mg/l) and 571.0�
0.81 (mg/l), respectively.
The concentration of Pb, Cd, Cr, Cu, Fe, Zn, Mg, Mn, Ca and K, in the sheep’s milk were 0.062�
0.03, 0.106� 0.11, 0.040� 0.01, 0.201� 0.10, 0.880� 0.31, 5.350� 0.50, 180� 1.20, 0.072�
0.01, 478� 3.10, and 593.96� 1.87, respectively

Full text

SOP TRANSACTIONS ON ANALYTICAL CHEMISTRY
In Press
SOP TRANSACTIONS ON ANALYTICAL CHEMISTRY
A Comparative Study on the
Physicochemical Parameters and Trace
Elements in Raw Milk Samples Collected
from Misurata- Libya
M.A. Elbagermi1*, A.I Alajtal1, H.G.M. Edwards2
1Department of Chemistry, Faculty of Science, University of Misurata, P.O. Box, 1338 Misurata, Libya
2Raman Spectroscopy Group, University Analytical Centre, Division of Chemical and Forensic Sciences, University of Bradford,
West Yorkshire, BD7 1DP, UK
*Corresponding author: m.elbagermi@yahoo.co.uk
Abstract:
This research work was carried out to compare the physicochemical parameters of milk samples
from four different animal species namely cow, goat, camel and sheep. Milk samples were
collected from different areas of Misurata, Libya and analyzed for the key physiochemical
parameters, pH, titratable acidity, total solids, ash, fat, protein and lactose. Furthermore in
this study the concentrations of Zinc (Zn), Cadmium (Cd), Chromium (Cr), Magnesium (Mg),
Manganese (Mn), Potassium (K), Calcium (Ca) Copper (Cu), Iron (Fe) and Lead (Pb) in similar
commercial milk specimens from the same area were determined using microwave plasma-
atomic emission spectrometry In fresh cow’s milk, the mean concentrations of Pb, Cd, Cr, Cu,
Fe, Zn, Mg, Mn, Ca and K were 0.13
±
0.19 (mg/l), 0.004
±
0.001 (mg/l), 0.04
±
0.01 (mg/l),
0.17
±
0.11 (mg/l), 0.72
±
0.02 (mg/l), 1.98
±
0.04 (mg/l), 214.00
±
0.20 (mg/l), 0.080
±
0.05
(mg/l), 423.0±3.5 (mg/l) and 427.0±2.5 (mg/l), respectively. While the mean concentration of
Pb, Cd, Cr, Cu, Fe, Zn, Mg, Mn, Ca and K, in the goat’s milk were 0.761
±
0.78 (mg/l), 0.085
±
0.02 (mg/l), 1.253
±
0.18 (mg/l), 0.400
±
0.08 (mg/l), 1.23
±
0.21 (mg/l), 3.110
±
0.15 (mg/l),
140.0
±
0.31 (mg/l), 0.097
±
0.07 (mg/l), 473
±
5.12 (mg/l) and 510
±
6.05 (mg/l), respectively.
The concentration of Pb, Cd, Cr, Cu, Fe, Zn, Mg, Mn, Ca and K, in the camel’s milk were 0.025
±
0.019 (mg/l), 0.091
±
0.05 (mg/l), 0.069
±
0.07 (mg/l), 0.080
±
0.05 (mg/l), 1.680
±
0.43 (mg/l),
5.380
±
1.17 (mg/l), 120.0
±
0.11 (mg/l), 0.094
±
0.04 (mg/l), 520.0
±
0.32 (mg/l) and 571.0
±
0.81 (mg/l), respectively.
The concentration of Pb, Cd, Cr, Cu, Fe, Zn, Mg, Mn, Ca and K, in the sheep’s milk were 0.062
±
0.03, 0.106
±
0.11, 0.040
±
0.01, 0.201
±
0.10, 0.880
±
0.31, 5.350
±
0.50, 180
±
1.20, 0.072
±
0.01, 478±3.10, and 593.96±1.87, respectively.
Keywords:
Cow Milk; Goat Milk; Camel Milk; Sheep Milk; Misurata; Heavy Metals; Fat; pH; Protein; Lactose
1

SOP TRANSACTIONS ON ANALYTICAL CHEMISTRY
1. INTRODUCTION
Milk is considered as a staple food since it is a good source for protein, fat and major minerals essential
for health; hence, milk and milk products are the main constituents of the daily diet, especially for
vulnerable groups such as infants, school age children and the elderly [
1
]. Several studies have reported
the distribution and occurrence of essential components in various animal milks [
2
,
3
]. The reported data
show that the components of selected milks vary considerably and that their composition appears to be
affected by animal source genetics as well as by physical and environmental factors.
Goat milk differs from cow or human milk in having better digestibility, alkalinity and buffering
capacity [
4
]. Sheep milk is an excellent raw material for the milk processing industry especially in cheese
production [
5
]. Sheep milk has a higher specific gravity, viscosity, refractive index, titratable acidity, and
lower freezing point compared with cow’s milk [6].
The consumption of camel milk is popular in North Africa and Middle East where it is known for its
medicinal and dietary properties [
7
]. These properties are now being more widely exploited for human
health, as it is in several countries from the ex-Soviet Union [
8
] and in other developing countries [
9
] ,
where camel milk is considered to have anti-cancer [
10
], hypo-allergic [
11
] and anti-diabetic properties
[
12
]. A high content in unsaturated fatty acids contributes to its overall dietary quality [
13
,
14
]. The low
quantity of ß-casein and the lack of ß -lactoglobulin are linked to the hypo-allergic effect of camel milk.
Other components such as lactoferrin, immunoglobulins, lysozyme and vitamin C were reported to play a
central part in the determination of these properties [15,16].
The elemental composition of cow’s milk is generally unknown. It has been reported that the content
of the main mineral components,such as Ca, P, K, Na, Mg, Cl, S, is not diversified and undergoes only
slight changes depending on the lactation phase and the quality of nutrition [
1
], in particular under the
influence of applied mineral additives or environmental conditions, mainly chemical pollutants [
2
]. Flynn
[
3
] reported that in cow’s milk the content of mineral components averaged 7.3 g/l, but Hurley [
17
]
pointed out that the macroelements (Ca, P, Mg, Na, Cl and S) in milk are present in quantities ca. 0.578%
and their concentration is not diversified. Similarly, the low level concentrations of nickel (0.027 mg/l),
iron (0.45 mg/l) or silicon (1.43 mg/l) are not changed under the influence of animal feed supplementation.
However, Wnuk et al. [
18
] stated that in the case of mineral deficiency in this feed, some changes in the
macro element concentration in milk such as Ca, P, Mg, Na and K were observed
The content of microelements and trace elements in cow milk was recently more widely studied, in
particular in industrialized and polluted regions, since it is considered a good bioindicator of pollution of
the agricultural environment [
19
,
20
]. Therefore, the quality of milk is continuously monitored by the
National Veterinary Institute of Libya, and some elements, in particular toxic metals such as As, Cd, Hg,
Pb , are controlled in milk.
The aim of the present study was to assess and compare the physicochemical parameters of milk
samples collected from cows, goats, camels and sheep in Misurata- Libya.
2. MATERIAL AND METHODS
The studies were carried out on a population of cows, goats, camels and sheep in full lactation period
in animals between 4 and 12 years old.
2

A Comparative Study on the Physicochemical Parameters and Trace Elements in Raw Milk Samples Collected
from Misurata- Libya
2.1 Milk Sampling and Analysis
Milk samples were collected from the cows, goats, camels and sheep in farms located in the areas under
study. Samples were collected immediately after milking and the samples were taken 8 times in a month.
Milk samples were collected in 25 ml clean sterilized plastic bottles. Prior to milk collection, the udder
was liberally washed with water and dried to avoid contamination. Following washing of the udder, the
milk samples were collected directly in the bottle and the samples were kept frozen at -4
o
C until analysis.
2.2 Chemical Analysis
Fat, protein content titratable acidity, lactose, total solids (T.S), hydrogen peroxide content and ash
were determined according to the AOAC method, [
21
]. The pH value of milk samples was measured by
using a Knick-Digital pH meter model 646.
The measurements of total acidity, protein content, hydrogen peroxide content and heavy metals Pb,
Cd, Cr, Cu, Fe, Zn, Mg, Mn, Ca and K were undertaken by the following techniques:
⇒Titrimetric method with NaOH as titrant for determining the total acidity;
⇒
Titrimetric method with Na
2
S
2
O
3
as titrant for determining hydrogen peroxide content of milk
samples;
⇒- Kjeldahl method for protein content;
⇒Atomic emission spectrometry for determining metals, after a mineralization step.
Collected milk samples were subjected to wet digestion by the method as described in the literature
[22].
One gram of each milk sample was taken into a 100 ml digestion flasks and 10 ml of concentrated nitric
acid (Riedel-de Haen) was added. The contents of the flask were heated for 20 min. After heating, the
sample was cooled at room temperature and after adding 5 ml perchloric acid was heated vigorously until
white fumes appeared and the sample volume was reduced to 2–3 ml. The final volume was made to 50
ml by adding re-distilled water. The heavy metals concentration in the prepared samples was determined
by using microwave plasma- atomic emission spectrometry (Agilent 4100 MP-AMS).
Protein content was estimated by a formal titration method [
23
]. Lactose content was determined by
using the Fehling’s solution method [24].
3. RESULTS AND DISCUSSION
Immediately after the collection of milk samples, the pH of each sample was determined.
pH: The values of pH of milk samples of different species are shown in Table 1.
The results showed that pH values were in the range of 6.51659 in cow milk, 6.38-6.51 in goat milk,
6.23-6.54 in camel milk and 6.61-6.72 in sheep milk.
The significant differences between the means were calculated by one-way Analysis of Variance
3

SOP TRANSACTIONS ON ANALYTICAL CHEMISTRY
Table 1. pH values of milk samples collected from cow, goat, camel and sheep.
Milk samples pH values
Min Max. Mean SD(±)
Cow 6.51 6.59 6.55 0.03
Goat 6.38 6.51 6.50 0.04
Camel 6.23 6.54 6.42 0.07
Sheep 6.61 6.72 6.66 0.02
(ANOVA). The results showed that the pH values of milk samples collected from cow, camel, goat and
sheep were non-significantly (p
>
0.05) different from each other. pH values found in cow milk were
in agreement with the findings of Kanwal et al. [
25
] and Enb et al. [
26
]. pH values of goat milk were
similar to that reported by Sawaya et al. [
27
]. pH values of sheep milk were similar to that reported by
Kurkdjian and Gabrielian [28]; Haenlein and Wendorff [29].
Total solids:
The concentration of total solids in the milk samples collected from camel cow, goat and
sheep is given in
Table 2
. These results illustrated that the concentration of total solids was in the range
of 11.18-1387% in cow milk, 12.17-14.11% in goat milk 15351787% in camel milk, and 1689-1915%
in sheep milk. The concentration of total solids in sheep milk was significantly (p
<
0.001) higher than
that in cow and goat milk Statistical analysis showed non-significant (p >0.05) differences between the
concentration of total solids in camel and sheep milk, cow and goat milk.
The concentration of total solids found in cow milk during this investigation was in line with the
findings of Imranet al. [
30
], Enb et al. [
26
] and Mahboba and Zubeir [
31
]. The concentration of total
solids found in goat milk was similar to that reported by Kanwal et al. [
25
] and Imran et al. [
30
]. The
concentration of total solids found in sheep milk was similar to the findings of Talevski et al. [32].
Table 2. The concentration of total solids in milk samples collected from cow, goat, camel and sheep.
Milk samples Total solids (%)
Min Max. Mean SD(±)
Cow 11.18 13.87 13.12 0.35
Goat 12.17 14.11 13.20 0.15
Camel 15.35 17.87 16.89 0.31
Sheep 16.89 19.15 18.75 0.27
Titratable acidity:
The values of titratble acidity of milk samples collected from cow, goat, camel and
sheep milk samples are given in Table 3.
It was observed from our results that the values of titratable acidity were in the range of 0.15-0.19%
in cow milk, 0.14- 0.18% in goat milk, 0.16- 0.18% in camel milk and 0.21-0.26% in sheep milk. The
values of titratable acidity of sheep milk were higher than that of cow, camel and goat milk at a highly
significant (p
<
0.001) level. The difference between the values of titratable acidity of cow, camel and
goat milk was non-significant (p >0.05).
The values of titratable acidity in cow milk were in line with that reported in the literature [
26
,
31
]. The
titratable acidity values of goat milk were similar to the findings of Sawaya et al. [
27
]. The values of
titratable acidity of sheep milk were similar to that reported by [
28
,
29
]. The acidity of milk is due the
presence of lactic acid, citric acid and phosphoric acid [32].
Ash:
The ash content in milk samples collected from cow, goat, camel and sheep is given in
Table
4

A Comparative Study on the Physicochemical Parameters and Trace Elements in Raw Milk Samples Collected
from Misurata- Libya
Table 3. Titratable acidity of milk samples collected from cow, goat, camel and sheep.
Milk samples Titratable acidity (%)
Min Max. Mean SD(±)
Cow 0.15 0.19 0.18 0.02
Goat 0.14 0.18 0.17 0.01
Camel 0.16 0.18 0.17 0.01
Sheep 0.21 0.26 0.23 0.03
4
. The results of this study revealed that the ash content was in the range of 0.45-0.82% in cow milk,
0.57-088% in goat milk, 0.62-0.86% in camel milk and 0.72-088% in sheep milk. The amount of ash
content in cow milk was lower than that in goat, camel and sheep milk at a highly significant (p
<
0.001)
level. There was a significant difference (p
<
0.05) between the amount of ash content in cow and goat
milk. There was a non-significant (p
>
0.05) difference between the amount of ash content in the milk
samples collected from camels, goats and sheep.
Table 4. Ash content in milk samples collected from cow, goat, camel and sheep.
Milk samples Ash (%)
Min Max. Mean SD(±)
Cow 0.45 0.82 0.63 0.06
Goat 0.57 0.88 0.79 0.09
Camel 0.62 0.86 0.82 0.11
Sheep 0.72 0.88 0.85 0.05
Fat:
The fat content in milk samples collected from cows, goats, camels and sheep is given in
Table 5
.
The results illustrated that the fat content was in the range of 710851% in cow milk, 3.25-4.68% in goat
milk, 1.75 -5.21% in camel milk and 6.21-6.41% in sheep milk.
The amount of fat content in cow milk and sheep milk was higher than that in the milk of other species
at highly significant (p
<
0.001) level. The amount of fat content in sheep milk was higher than that in
milk of camel and goat but lower than that in cow milk at a highly significant (p
<
0.001) level. There
was a non-significant (p >0.05) difference between the amount of fat content in cow and sheep milk.
Table 5. Fat content in milk samples collected from cow, goat, camel and sheep.
Milk samples Fat (%)
Min Max. Mean SD(±)
Cow 7.10 8.51 6.56 0.34
Goat 3.25 4.68 4.23 0.31
Camel 1.75 5.21 3.14 0.61
Sheep 6.21 6.56 6.41 0.21
Protein:
Protein content in milk samples collected from cow, goat, camel and sheep is given in
Table
6.
According to these results the protein content was in the range of 3.13-3.98% in cow milk, 2.67-3.57%
in goat milk, 2.87-4.12% in camel milk and 5.00-5.61% in sheep milk. The amount of protein content
in sheep milk was higher than that in the milk of other species at a highly significant (p
<
0.001) level.
There was a non-significant (p
>
0.05) difference between the amount of protein content in cow, goat and
5

SOP TRANSACTIONS ON ANALYTICAL CHEMISTRY
Table 6. Protein content in milk samples collected from cow, goat, camel and sheep.
Milk samples Protein (%)
Min Max. Mean SD(±)
Cow 3.13 3.98 3.32 0.24
Goat 2.67 3.57 3.10 0.11
Camel 2.87 4.12 3.12 0.31
Sheep 5.00 5.61 5.41 0.01
camel milk.
Lactose:
Lactose content in milk samples collected from cow, goat, camel and sheep is given in
Table
7.
Table 7. Lactose content in milk samples collected from cow, goat, camel and sheep.
Milk samples Lactose (%)
Min Max. Mean SD(±)
Cow 4.10 5.24 4.50 0.38
Goat 3.89 4.73 4.31 0.27
Camel 3.10 6.73 5.21 0.24
Sheep 4.42 5.31 4.75 0.21
Lactose is the major carbohydrate in milk. The content of lactose in our study was in the range of
4.10-5.24% in cow milk, 3.89-4.73% in goat milk, 3.10-6.73% in camel milk and 4.42-5.31% in sheep
milk. The amount of lactose content in camel milk was higher than that in the milk of other species at
a highly significant (p
<
0.001) level. There was a non-significant (p
>
0.05) difference between the
amount of lactose content in cow, goat and sheep milk.
Heavy metals:
The results of the present study for the ten trace elements in the milk samples collected
from different areas in Misurata - Libya are given in Table 8.
Table 8. Elemental concentration in fresh cow, goat, camel and sheep milk.
Element (mg/l) Cow milk Goat milk Camel milk Sheep milk
Pb 0.030±0.19 0.61 ±0.78 0.025 ±0.019 0.062±0.03
Cd 0.004±0.001 0.085 ±0.02 0.091±0.05 0.106±0.11
Cr 0.040±0.01 1.253 ±0.18 0.069±0.07 0.040±0.01
Cu 0.170±0.11 0.400±0.08 0.080 ±0.05 0.201±0.10
Fe 0.720±0.02 1.23±0.21 1.680 ±0.43 0.880±0.31
Zn 1.980±0.04 3.110±0.15 5.380 ±1.17 5.350±0.50
Mg 214.00±0.20 140.0±0.31 120.0 ±0.11 180±1.20
Mn 0.080±0.05 0.097±0.07 0.094 ±0.04 0.072±0.01
Ca 423.0±3.45 473±5.12 520.0 ±0.32 478.00±3.10
K 427.0±2.46 510±6.05 571.0±0.81 593.96±1.87
In fresh cow’s milk, the mean concentrations of Pb, Cd, Cr, Cu, Fe, Zn, Mg, Mn, Ca and K were
0.130±0.19 (mg/l), 0.004±0.001 (mg/l), 0.040±0.01 (mg/l), 0.170±0.11 (mg/l), 0.720±0.02 (mg/l),
1.980
±
0.04 (mg/l), 214.00
±
0.20 (mg/l), 0.080
±
0.05 (mg/l), 423.0
±
3.45 (mg/l) and 427.0
±
2.46
(mg/l), respectively. The mean concentrations of Pb, Cd, Cr, Cu, Fe, Zn, Mg, Mn, Ca and K, in the goat
6

A Comparative Study on the Physicochemical Parameters and Trace Elements in Raw Milk Samples Collected
from Misurata- Libya
milk were .761
±
0.78 (mg/l), 0.085
±
0.02 (mg/l), 1.253
±
0.18 (mg/l), 0.400
±
0.08 (mg/l), 1.23
±
0.21
(mg/l), 3.110
±
0.15 (mg/l) 140.0
±
0.31 (mg/l), 0.097
±
0.07 (mg/l), 473
±
5.12 (mg/l) and 510
±
6.05
(mg/l), respectively. The concentrations of Pb, Cd, Cr, Cu, Fe, Zn, Mg, Mn, Ca and K, in the camel milk
were 0.025
±
0.019 (mg/l), 0.091
±
0.05 (mg/l), 0.069
±
0.07 (mg/l), 0.080
±
0.05 (mg/l) 1.680
±
0.43
(mg/l), 5.380
±
1.17 (mg/l) 120.0
±
0.11 (mg/l) 0.094
±
0.04 (mg/l) 520.0
±
0.32 (mg/l) and 571.0
±
0.81 (mg/l) respectively.
The concentrations of Pb, Cd, Cr, Cu, Fe, Zn, Mg, Mn, Ca and K, in the sheep milk were 0.062
±
0.03,
0.106
±
0.11, 0.040
±
0.01, 0.201
±
0.10, 0.880
±
0.31, 5.350
±
0.50, 180
±
1.20, 0.072
±
0.01, 478
±
3.10,
and 593.96±1.87, respectively.
The concentrations of lead and cadmium in sheep milk was higher than that in the milk of other species
at a highly significant (p <0.001) level.
The concentration of chromium in goat milk samples was higher than that in the milk of the other
animals The chromium concentration in goat milk was much higher than the literature values. The mean
concentration of Cr in goat milk is 1.253 mg/l. The values reported by Coni et al. as (0.03 mg/l) [
33
] and
Caggiano et al. as (0.15 mg/l) [
34
] are far less than the current findings (1.253
±
0.18 mg/l). The higher
value of Cr in goat milk found here compared with that reported in the literature may be due to the fact
that goats have a particular preference for nibbling the emerging shoots, leaves, nodes and the tender parts
of the plants where chromium deposits are determined to be in much higher concentration in these parts
[35].
The concentration of copper in camel milk was lower than in the other milk samples. The mean level of
Fe found in camel milk samples (1.680 mg/l) was higher than (p
\
0.05) those collected from the other milk
samples. The mean concentration of Zn in the cow, goat, camel and sheep milk samples was 1.980, 3.11,
5.36 and 5.35 mg/l, respectively. The concentration of magnesium in cow milk was higher than (p
\
0.05).
The manganese concentrations detected in goat milk samples was higher than those detected in the cow,
camel and sheep milk samples. The calcium concentrations in the camel milk samples were higher than
those detected in the cow, goat and sheep milk samples and the concentration of potassium in the sheep
milk samples was higher than those detected in the cow, goat and camel milk samples. The correlation
matrix between the studied minerals generally shows low coefficients of correlation; however, it was found
that calcium in the samples of raw cow’s milk was significantly correlated with potassium (
r
=0.530) and
zinc (
r
= 0.515), which suggests some biological or physiological relation among these essential minerals.
4. CONCLUSION
This study provides novel information on the physicochemical parameters and trace element contents
of cow, goat, and camel and sheep milk in Misurata / Libya and fulfils an important role by providing
bibliographical sources on the total composition of cow, goat, camel and sheep milk in Libya. All the
tested parameters were higher in sheep milk than cow, camel and goat milk: specific pH, titratable acidity,
ash, lactose and protein in sheep milk were all higher than those in cow, goat and camel milk but the fat in
cow milk was higher than that in sheep, goat and camel milk.
7

SOP TRANSACTIONS ON ANALYTICAL CHEMISTRY
References
[1]
J. E. Davies, V. H. Freed, F. W. Whittemore, et al., “Agromedical approach to pesticide management,”
University of Miami, 1986.
[2]
A. Kholif, S. Abo El-Nor, A. Abou-Arab, and H. El-Alamy, “Effect of spraying diazinon to control
the external parasites on the productive performance of dairy animals-1. Yield and composition of
buffaloes’ and friesian cows’ milks,” Egyptian Journal of Dairy Science, vol. 22, pp. 145–145, 1994.
[3]
A. Abou-Arab, “Effect of Ras cheese manufacturing on the stability of DDT and its metabolites,”
Food Chemistry, vol. 59, no. 1, pp. 115–119, 1997.
[4]
Y. Park, “Hypo-allergenic and therapeutic significance of goat milk,” Small Ruminant Research,
vol. 14, no. 2, pp. 151–159, 1994.
[5]
Y. Park, M. Ju
´
arez, M. Ramos, and G. Haenlein, “Physico-chemical characteristics of goat and sheep
milk,” Small Ruminant Research, vol. 68, no. 1, pp. 88–113, 2007.
[6]
G. F. Haenlein and W. L. Wendorff, “Sheep milk,” Handbook of Milk of Non-bovine Mammals,
pp. 137–194, 2006.
[7]
B. Faye, G. Konuspayeva, S. Messad, and G. Loiseau, “Discriminant milk components of Bactrian
camel (Camelus bactrianus), dromedary (Camelus dromedarius) and hybrids,” Dairy Science &
Technology, vol. 88, no. 6, pp. 607–617, 2008.
[8]
S. Kenzhebulat, B. Ermuhan, and A. Tleuov, “Composition of camel milk and its use in the treatment
of infectious diseases in human,” in Proceedings of the 2nd Camelid conference on Agroeconomics
of Camelid Farming, 2000.
[9]
G. Mal, D. Sena, V. Jain, and M. Sahani, “Therapeutic value of camel milk as a nutritional supplement
for multiple drug resistant (MDR) tuberculosis patients,” Israel Journal of Veterinary Medicine,
vol. 61, no. 3/4, p. 88, 2006.
[10]
N. Magjeed, “Corrective effect of milk camel on some cancer biomarkers in blood of rats intoxicated
with aflatoxin B1,” Journal of the Saudi Chemical society, vol. 9, pp. 253–263, 2005.
[11]
Y. Shabo, R. Barzel, M. Margoulis, and R. Yagil, “Camel milk for food allergies in children,”
IMAJ-RAMAT GAN-, vol. 7, no. 12, p. 796, 2005.
[12]
R. Agarwal, S. Swami, R. Beniwal, D. Kochar, M. Sahani, F. Tuteja, and S. Ghouri, “Effect of camel
milk on glycemic control, risk factors and diabetes quality of life in type-1 diabetes: A randomized
prospective controlled study,” Journal of Camel Practice and Research, vol. 10, no. 1, pp. 45–50,
2003.
[13]
N. Karray, C. Lopez, M. Ollivon, and H. Attia, “La mati
`
ere grasse du lait de dromadaire: composition,
microstructure et polymorphisme. Une revue,” Ol
´
eagineux, Corps Gras, Lipides, vol. 12, no. 5,
pp. 439–446, 2005.
[14]
G. Konuspayeva,
´
E. Lemarie, B. Faye, G. Loiseau, and D. Montet, “Fatty acid and cholesterol
composition of camel’s (Camelus bactrianus, Camelus dromedarius and hybrids) milk in Kazakhstan,”
Dairy Science and Technology, vol. 88, no. 3, pp. 327–340, 2008.
[15]
E. Elagamy, R. Ruppanner, A. Ismail, C. Champagne, and R. Assaf, “Purification and characterization
of lactoferrin, lactoperoxidase, lysozyme and immunoglobulins from camel’s milk,” International
Dairy Journal, vol. 6, no. 2, pp. 129–145, 1996.
[16]
G. Konuspayeva, B. Faye, G. Loiseau, and D. Levieux, “Lactoferrin and Immunoglobulin Contents in
Camel’s Milk ( Camelus bactrianus, Camelus dromedarius, and Hybrids) from Kazakhstan,” Journal
of Dairy Science, vol. 90, no. 1, pp. 38–46, 2007.
[17] W. Hurley and D. Morin, “Lactation biology,” Urbana: University of Illinois, 2000.
[18]
W. Wnuk, J. Odoj, H. Bis-Wencel, L. Saba, B. Nowakowicz-Debek, and T. Bombik, “Milk and
hair coat as indicators of macroelements content in cows at different stages of lactation,” Annales
8

A Comparative Study on the Physicochemical Parameters and Trace Elements in Raw Milk Samples Collected
from Misurata- Libya
Universitatis Mariae Curie-Skłodowska. Sectio EE: Zootechnica, vol. 21, no. 2, 2003.
[19]
J. Monkiewicz, J. Forster, H. Geringer, J. Napierala, Z. Jopek, E. Kucharczak, et al., “Preventing
overaccumulation of lead, cadmium, arsenic, copper and zinc in cows kept in polluted environment,”
Polish J Environ Stud, vol. 8, pp. 117–121, 1999.
[20]
G. Talevski, R.
ˇ
Cobanova-Vasilevska, S. Srbinovska, and Z. Sireta, “Quality of the sheep milk
as a raw material in dairy industry of Macedonia,” Biotechnology in Animal Husbandry, vol. 25,
no. 5-6-2, pp. 971–977, 2009.
[21]
A. international, Official methods of analysis of AOAC International. 17th Edn., Association of
Official Analytical Chemists, Washington. DC, 2000.
[22]
L. A. RICHARDS, “Diagnosis and improvement of saline and alkaline soils,” IBH Publications
Company, 1968.
[23]
C. L. Davide, Laboratory guide in dairy chemistry practicals. Dairy Training and Research Institute,
University of the Philppines, 1977.
[24]
H. O. Triebold, “Quantitative analysis with applications to agricultural and food products,” D. van
Nostrand Company, pp. 204–221, 2000.
[25]
R. Kanwal, T. Ahmed, and B. Mirza, “Comparative analysis of quality of milk collected from buffalo,
cow, goat and sheep of Rawalpindi/Islamabad region in Pakistan,” Asian Journal of Plant Sciences,
vol. 3, no. 3, pp. 300–305, 2004.
[26]
A. Enb, M. Abou Donia, N. Abd-Rabou, A. Abou-Arab, and M. El-Senaity, “Chemical composition
of raw milk and heavy metals behavior during processing of milk products,” Global Veterinaria,
vol. 3, no. 3, pp. 268–275, 2009.
[27]
W. Sawaya, W. Safi, A. Al-Shalhat, and M. Al-Mohammad, “Chemical composition and nutritive
value of goat milk,” Journal of Dairy Science, vol. 67, no. 8, pp. 1655–1659, 1984.
[28]
V. Kurkdjian and T. Gabrielian, “Physical and chemical properties and composition of ewe’s milk,”
Proceedings of the XVI Int. Dairy Congr., vol. AP, pp. 197–208, 1962.
[29]
G. F. Haenlein and W. L. Wendorff, “Sheep milk,” Handbook of Milk of Non-bovine Mammals,
pp. 137–194, 2006.
[30]
M. Imran, H. Khan, S. S. Hassan, and R. Khan, “Physicochemical characteristics of various milk
samples available in Pakistan,” Journal of Zhejiang University Science B, vol. 9, no. 7, pp. 546–551,
2008.
[31]
M. I. Ahmed and I. E. El Zubeir, “The compositional quality of raw milk produced by some dairy
cows farms in Khartoum State, Sudan,” Research Journal of Agriculture and Biological Sciences,
vol. 3, no. 6, pp. 902–906, 2007.
[32]
W. Boylan, T. Makhambera, L. Kamwanja, H. Swartz, and S. Patten, “Breeding goats in the tropics
to enhance child nutrition and health,” in Proceedings of the VI International Conference on Goats,
Beijing, China, vol. 1, pp. 51–53, 1996.
[33]
E. Coni, A. Bocca, P. Coppolelli, S. Caroli, C. Cavallucci, and M. T. Marinucci, “Minor and
trace element content in sheep and goat milk and dairy products,” Food Chemistry, vol. 57, no. 2,
pp. 253–260, 1996.
[34]
R. Caggiano, S. Sabia, M. DEmilio, M. Macchiato, A. Anastasio, M. Ragosta, and S. Paino,
“Metal levels in fodder, milk, dairy products, and tissues sampled in ovine farms of Southern Italy,”
Environmental Research, vol. 99, no. 1, pp. 48–57, 2005.
[35]
I. H. Shah, Irrigation of Crops with Sewage Effluent: Implications and Movement of Pb and Cr as
Affected by Soil Texture, Lime, Gypsum and Organic Matter. PhD thesis, University of Agriculture,
Faisalabad, 2000.
9