127 
 

Journal homepage: www.fia.usv.ro/fiajournal 
Journal of Faculty of Food Engineering,  

Ştefan cel Mare University of Suceava, Romania  
Volume XIII, Issue 2  – 2014, pag.  127 - 133  

 

 
IN FLU ENCE OF DI FFER ENT C HE M ICAL A GE NT S  

ON THE A DUL TE RE D M ILK PHYS ICA L PRO PER TIES CORRE CT ION  

 
*Mircea OROIAN1, Daniel BERNICU1 

 
1Food Engineering Faculty, Stefan cel Mare University of Suceava,  

m.oroian@fia.usv.ro 
*Corresponding author 

Received April 7th 2014, accepted May 7th 2014 
 

 
Abstract: In the milk industry, one of the most common frauds is the mixing of milk with water with 
the goal of improving the quantity. After the water adding to the milk, the counterfitert adds different 
substances to bring the physical properties in the right range.  The aim of this study is to evaluate the 
influence of adulteration agents on the milk physical properties. For this purpose, the milk was 
adultered with different percentages of water (0, 5, 10 and 20 % respectively). The milk adultered with 
20 % water was mixed with four substantces in order to bring the density and crioscopic temperature 
in the right range. The substantces used for the density and crioscopic temperature corrections were: 
NaCl, NH4Cl, NH4NO3 and CH4ON2. The NaCl, NH4Cl, NH4NO3 and CH4ON2 were mixed with the 
milk substituted with 20% eater in three different levels (0.25, 0.5 and 1% respectively in the case of 
NaCl, and 0.05, 0.10 and 0.20% respectively in the case of the other adulterants). All the four 
chemical substances brought the density and crioscopic temperature in the normal range but in 
different percentages.   
 
Keywords: milk, adulteration, density, crioscopic temperature 
 
 
1. Introduction 

 
One of the most consumed food products 
in the world is the bovine’s milk. The 
bovine’s milk contains 3-4% fat [1], and its 
fat contains 98% triacylglycerols and 2% 
of other lipids such as diacylglycerols, 
phospholipids and cholesterol [2]. The 
milk industry challenges a growing 
number of frauds, because of the high 
nutritional value of milk, that have an 
effect on the process of these products [3]. 
The principal adulteratios in the case of 
milk are: the milk dilution with water, fat 

partial or total removal, skimmed milk 
powder addition, milk from other species 
addition, chemical substances addition for 
neutralisation and conservation, fertilizers 
addition and dyes addition, respectively [4, 
5]. 
Another fraudulent practise in the milk 
industry happened in 2007 and 2008 when 
it was found melamine into the milk. These 
incidents happened in China [6, 7].  
The milk density is the ratio of its mass 
and volume, and is expressed into g/cm3. 
The milk density is influenced by the 
temperature, species, diet, the milk 



Food and Environment Safety - Journal of Faculty of Food Engineering, Ştefan cel Mare University - Suceava 
Volume XIII, Issue 2 – 2014 

 
 

 
M ir ce a  OR OI AN ,  D a nie l B E RN IC U,  I n fl u e nc e  of  d if f e r e n t  ch em i c a l  ag e nt s  on  t h e ad ul t er ed  m i l k 
p h y si ca l  p r o pe r t i e s c o r r e ct i on , Issue 2 - 2014, pag. 127 - 133 

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chemical composition, adulteration and 
cow’s diseases. The cow milk density is 
ranging between 1.029 – 1.033 g/cm3. In 
the case of water adding into the milk, the 
density is decreasing, while in the case of 
fat removal the density is increasing [4]. 
Another important physical parameter of 
milk is crioscopic temperature. The 
crioscopic temperature is defined as the 
temperature where the milk is freezing. 
The value of crioscopic temperature is 
influenced by: the solubile substances 
concentration (lactose, mineral salts, 
nitrogen substances which form the 
neproteic nitrogen), substances added for 
the acidity reduction (carbonates), 
substances added for the dry matter 
increasing, water adding to the milk. The 
crioscopic temperature ranges between      
-0.512 and -0.560 °C. The crioscopic 
temperature should be corrected in 
function of milk acidity [4]. 
In the case of milk substition with water 
are added different substances (NaCl, 
NH4Cl, NH4NO3 and CH4ON2) in order to 
correct their physical parameters [8]. 
The aim of this study is to evaluate the 
influence of adulteration agents on the 
physical properties of milk.  
 
2. Materials and methods 
2.1 Materials 
Milk (3.5 % fat), distilled water, NaCl, 
NH4Cl, NH4NO3 and CH4ON2. 

 
2.2. Methods 
Density determination 
The milk density was measured using the 
picnometer method.  
 

 

Crioscopic temperature determination 
The crioscopic temperature was measured 
using the CryoStar I device. 2 ml of 
sample was placed into the device till the 
crioscopic temperature is achieved and 
displayed on the device display. 
 
2.3. Milk adulteration 
The milk was adultered with distilled water 
in different percentages (0, 5, 10 and 20% 
respectively). The sample with 20% water 
was mixed with different concentractions 
of NaCl, NH4Cl, NH4NO3 and CH4ON2. 

 
3. Results and discussions 

 
3.1. The water influence on the milk 
physical properties  
It is well known that if water is added to 
the milk, its density is decreasing with the 
increasing of the water percentage added. 
In our case the adding of water, in different 
percentages (ranging from 0 to 20%) 
decreased the magnitude of the density. In 
the table 1 is presented the milk density of 
the milk and of the adulterated samples. 

 
Table 1.  

Milk density evolution with different 
percentages od water 

Sample Density (g/cm3) 
Blanck 1.030 
Milk with 5% water 1.027 
Milk with 10% water 1.025 
Milk with 20% water 1.021 

 
The substition of milk with water is 
making that the density to not be in the 
normal range. If the milk is substituted 
with 20 % water, the density is decreasing 
with 0.87 %. 
The crioscopic temperature of the 
adulterated milk increased with the 



Food and Environment Safety - Journal of Faculty of Food Engineering, Ştefan cel Mare University - Suceava 
Volume XIII, Issue 2 – 2014 

 
 

 
M ir ce a  OR OI AN ,  D a nie l B E RN IC U,  I n fl u e nc e  of  d if f e r e n t  ch em i c a l  ag e nt s  on  t h e ad ul t er ed  m i l k 
p h y si ca l  p r o pe r t i e s c o r r e ct i on , Issue 2 - 2014, pag. 127 - 133 

129 
 

increasing of the water percentage. The 
increasing of the crioscopic temperature is 
caused by the dilution of the chemical 
parameters concentrations. In the table 2 is 
presented the milk crioscopic temperature 
of the milk and of the adulterated samples. 

 
Table 2.  

Milk crioscopic temperature evolution 
with different percentages od water 

Sample Crioscopic 
temperature (°C) 

Blanck -0.5398 
Milk with 5% water -0.5220 
Milk with 10% water -0.4837 
Milk with 20% water -0.4296 
From the data presented in the table 2 we 
can see that the sample adultered with 5% 
water has the crioscopic temperature in the 
normal range, while in the case of the 
samples with 10 and 20 % water, the 
crioscopic temperature is not the right 
range. The addition of 20% water is 
increasing the crioscopic temperature of 
milk with 25.65%. 

 
3.2. The influence of NaCl on the 
physical properties of milk adulterated 
with 20 % water  
The NaCl is added into the milk for 
masking the water adding into the milk and 
for the correction of the density. 
In this paper, it was added NaCl to the 
milk adultered with 20% water in different 
concentrations: 0.25, 0.5 and 1 % 
respectively in order to achieve the 
optimum quantity for the density and 
crioscopic temperature correction. 
In the figure 1 is presented the density of 
the sample adultered with 20% water in 
which was added different concentrations 
of NaCl. 

 

 
Fig. 1. The density of milk adultered with 20% 
mixed with different concentrations of NaCl, A: 
Milk with 20% water, B: Milk with 20% water 
with 0.25% NaCl, C: Milk with 20% water with 

0.50% NaCl, D: Milk with 20% water with 
1.00% NaCl 

The addition of NaCl into the adultered 
milk increased the density, but the quantity 
of NaCl needed for achieving the right 
density is lower than the quantity studied 
in the present paper. The quantity should 
be around 0.1% NaCl. The addition of 1% 
NaCl increased the density with 5.38%. 

 
Fig. 2. The crioscopic temperature of milk 

adultered with 20% mixed with different 
concentrations of NaCl: A: Milk with 20% 
water, B: Milk with 20% water with 0.25% 
NaCl, C: Milk with 20% water with 0.50% 

NaCl, D: Milk with 20% water with 1.00% NaCl 

0.95 1 1.05 1.1

A

B

C

D

Density (g/cm3)

Sa
m

pl
e

-3 -2 -1 0

A

B

C

D

Crioscopic temperature (°C)

Sa
m

pl
e



Food and Environment Safety - Journal of Faculty of Food Engineering, Ştefan cel Mare University - Suceava 
Volume XIII, Issue 2 – 2014 

 
 

 
M ir ce a  OR OI AN ,  D a nie l B E RN IC U,  I n fl u e nc e  of  d if f e r e n t  ch em i c a l  ag e nt s  on  t h e ad ul t er ed  m i l k 
p h y si ca l  p r o pe r t i e s c o r r e ct i on , Issue 2 - 2014, pag. 127 - 133 

130 
 

In the figure 2 is presented the crioscopic 
temperature of the sample adultered with 
20% water in which was added different 
concentrations of NaCl. 
The addition of NaCl into the adultered 
milk decreased the crioscopic temperature, 
but the quantity of NaCl needed for 
achieving the right crioscopic temperature 
is lower than the quantity studied in the 
present paper. The quantity should be 
around 0.1% NaCl, like in the case of the 
density. The addition of 1% NaCl 
decreased the crioscopic temperature with 
477.4 %. 

 
3.3. The influence of NH4Cl on the 
physical properties of milk adulterated 
with 20 % water  
The NH4Cl is added, like NaCl too, into 
the milk for masking the water adding into 
the milk and for the correction of the 
density. 
In this paper, it was added NH4Cl to the 
milk adultered with 20% water in different 
concentrations: 0.05, 0.10 and 0.20 % 
respectively in order to achieve the 
optimum quantity for the density and 
crioscopic temperature correction. 
In the table 3 is presented the density of 
the sample adultered with 20% water in 
which was added different concentrations 
of NH4Cl. 
The addition of NH4Cl into the adultered 
milk increased the density, it seems that 
the addition of 0.05% is bringing the milk 
density into the desired range. The others 
percentages studied were to big for 
bringing the density in the normal range. 
The addition of 0.20% NH4Cl increased 
the density with 1.37%. 

 
 

Table 3.  
The density of milk adultered with 20% 

mixed with different concentrations of NH4Cl 
Sample Density (g/cm3) 
Milk with 20% water 1.021 
Milk with 20% water with 
0.05% NH4Cl 

1.031 

Milk with 20% water with 
0.10% NH4Cl 

1.034 

Milk with 20% water with 
0.20% NH4Cl 

1.035 

 
In the table 4 is presented the crioscopic 
temperature of the sample adultered with 
20% water in which was added different 
concentrations of NH4Cl. 

 
Table 4.  

The crioscopic temperature of milk 
adultered with 20% mixed with different 

concentrations of NH4Cl 
Sample Crioscopic 

temperature (°C) 
Milk with 20% water -0.4296 
Milk with 20% water with 
0.05% NH4Cl 

-0.5869 

Milk with 20% water with 
0.10% NH4Cl 

-0.6687 

Milk with 20% water with 
0.20% NH4Cl 

-0.9050 

 
The addition of NH4Cl into the adultered 
milk decreased the crioscopic temperature, 
but the quantity of NH4Cl needed for 
achieving the right crioscopic temperature 
is lower than the quantity studied in the 
present paper. The quantity should be 
around 0.03% NH4Cl. The addition of 0.20 
% NH4Cl decreased the crioscopic 
temperature with 110.66 %. 

 
3.4. The influence of NH4NO3 on the 
physical properties of milk adulterated 
with 20 % water  



Food and Environment Safety - Journal of Faculty of Food Engineering, Ştefan cel Mare University - Suceava 
Volume XIII, Issue 2 – 2014 

 
 

 
M ir ce a  OR OI AN ,  D a nie l B E RN IC U,  I n fl u e nc e  of  d if f e r e n t  ch em i c a l  ag e nt s  on  t h e ad ul t er ed  m i l k 
p h y si ca l  p r o pe r t i e s c o r r e ct i on , Issue 2 - 2014, pag. 127 - 133 

131 
 

The NH4NO3 is added, like NaCl and 
NH4Cl too, into the milk for masking the 
water adding into the milk and for the 
correction of the density. 
In this paper, it was added NH4NO3 to the 
milk adultered with 20% water in different 
concentrations: 0.05, 0.10 and 0.20 % 
respectively in order to achieve the 
optimum quantity for the density and 
crioscopic temperature correction. 
In the figure 3 is presented the density of 
the sample adultered with 20% water in 
which was added different concentrations 
of NH4NO3. 

 
 

Fig. 3. The density of milk adultered with 
20% mixed with different concentrations of 

NH4NO3, A: Milk with 20% water, B: Milk with 
20% water with 0.05% NH4NO3, C: Milk with 
20% water with 0.10% NH4NO3, D: Milk with 

20% water with 0.20% NH4NO3 
 

The addition of NH4NO3 into the adultered 
milk increased the density, it seems that 
the addition of 0.05 and 0.10%  NH4NO3 is 

bringing the milk density into the desired 
range. In the case of 0.20% NH4NO3 the 
value of the density is appropriated to the 
normal value. The addition of 0.20% 
NH4NO3 increased the density with 1.27%. 
In thefigure 4 is presented the crioscopic 
temperature of the sample adultered with 
20% water in which was added different 
concentrations of NH4NO3. 

 

 
 

Fig. 4. The crioscopic temperature of milk 
adultered with 20% mixed with different 

concentrations of NH4NO3: A: Milk with 20% 
water, B: Milk with 20% water with 0.05% 

NH4NO3, C: Milk with 20% water with 0.10% 
NH4NO3, D: Milk with 20% water with 0.20% 

NH4NO3 
 
The addition of NH4NO3 into the adultered 
milk decreased the crioscopic temperature, 
it seems that the addition of 0.05% of this 
adulterant brings the value in the normal 
range. The addition of 0.20 % NH4NO3 
decreased the crioscopic temperature with 
73.16 %. 

 

1.01 1.02 1.03 1.04

A

B

C

D

Density (g/cm3)

Sa
m

pl
e

-0.8 -0.6 -0.4 -0.2 0

A

B

C

D

Crioscopic temperature (°C)

Sa
m

pl
e



Food and Environment Safety - Journal of Faculty of Food Engineering, Ştefan cel Mare University - Suceava 
Volume XIII, Issue 2 – 2014 

 
 

 
M ir ce a  OR OI AN ,  D a nie l B E RN IC U,  I n fl u e nc e  of  d if f e r e n t  ch em i c a l  ag e nt s  on  t h e ad ul t er ed  m i l k 
p h y si ca l  p r o pe r t i e s c o r r e ct i on , Issue 2 - 2014, pag. 127 - 133 

132 
 

3.5. The influence of CH4ON2 on the 
physical properties of milk adulterated 
with 20 % water  
 
The CH4ON2 is added, like NaCl, NH4NO 
and NH4Cl too, into the milk for masking 
the water adding into the milk and for the 
correction of the density. 
In this paper, it was added CH4ON2 to the 
milk adultered with 20% water in different 
concentrations: 0.05, 0.10 and 0.20 % 
respectively in order to achieve the 
optimum quantity for the density and 
crioscopic temperature correction. 
In the table 5 is presented the density of 
the sample adultered with 20% water in 
which was added different concentrations 
of CH4ON2. 

 
Table 5.  

The density of milk adultered with 20% 
mixed with different concentrations of 

CH4ON2 
Sample Density (g/cm3) 
Milk with 20% water 1.021 
Milk with 20% water with 
0.05% CH4ON2 

1.032 

Milk with 20% water with 
0.10% CH4ON2 

1.034 

Milk with 20% water with 
0.20% CH4ON2 

1.035 

 
The addition of CH4ON2 into the adultered 
milk increased the density, it seems that 
the addition of 0.05 CH4ON2 is bringing 
the milk density into the desired range. In 
the case of 0.10% CH4ON2 the value of the 
density is appropriated to the normal value. 
The addition of 0.20% CH4ON2 increased 
the density with 1.35%. 
In the table 6 is presented the crioscopic 
temperature of the sample adultered with 

20% water in which was added different 
concentrations of CH4ON2. 

 
Table 6. 

The crioscopic temperature of milk 
adultered with 20% mixed with different 

concentrations of CH4ON2 
Sample Crioscopic 

temperature (°C) 
Milk with 20% water -0.4296 
Milk with 20% water with 
0.05% CH4ON2 

-0.4916 

Milk with 20% water with 
0.10% CH4ON2 

-0.5410 

Milk with 20% water with 
0.20% CH4ON2 

-0.6794 

 
The addition of CH4ON2 into the adultered 
milk decreased the crioscopic temperature, 
it seems that the addition of 0.10% of this 
adulterant brings the value in the normal 
range. The addition of 0.20 % CH4ON2 
decreased the crioscopic temperature with 
58.14 %. 
 
4. Conclusions 
 
The milk adulteration is one of the 
common adulterations of food products. 
The substitution of milk with water is 
leading to the modification of the physical 
parameters. In this paper we studied the 
influence of different adulterants on the 
physical properties of the milk substituted 
with 20% water. The substances used for 
the density and crioscopic temperature are 
useful for the correction of the two 
parameters. All the four adulterants (NaCl, 
NH4Cl, NH4NO3 and CH4ON2) brought the 
density and the crioscopic temperature in 
the normal range. For the corrections of the 
density is needed 0.1% NaCl or 0.05% 
CH4ON2, 0.05% NH4NO3 or 0.05% 



Food and Environment Safety - Journal of Faculty of Food Engineering, Ştefan cel Mare University - Suceava 
Volume XIII, Issue 2 – 2014 

 
 

 
M ir ce a  OR OI AN ,  D a nie l B E RN IC U,  I n fl u e nc e  of  d if f e r e n t  ch em i c a l  ag e nt s  on  t h e ad ul t er ed  m i l k 
p h y si ca l  p r o pe r t i e s c o r r e ct i on , Issue 2 - 2014, pag. 127 - 133 

133 
 

NH4Cl. In the case of the crioscopic 
temperature is needed 0.1% NaCl or 0.10% 
CH4ON2 or 0.05% NH4NO3 or 0.05% 
NH4Cl for the corrections. The addition of 
NaCl in the milk is not leading to a health 
issue, but the other three substances must 
not be presented in the milk.  
 
5. References 
 
[1] BOTARO, B. G., LIMA, Y. V. R., AQUINO, 

A. A., SANTOS, M. V., Effect of beta-
lactoglobulin polymorphism and seasonality 
on bovine milk composition, Journal of Dairy 
Research, 75, 176-181, (2008) 

[2] GARCIA, J. S., SANVIDO, G. B., SARAIVA, 
S. A., ZACCA, J. J., COSSO, R. G., 
EBERLIN, M. N., Bovine milk powder 
adulteration with vegetable oils or fats 
revealed by MALDI-QTOF MS, Food 
Chemistry, 131(2), 722-726, (2012) 

[3] CALVANO, C. D., DE CEGLIE, C., ARESTA, 
A., FACCHINI, L. A., ZAMBONI, C. G., 
MALDI – TOF mass spectrometric 
determination of intact phospolipids as 
markers of illegal bovine milk adulteration of 
high-quality milk, Analytical and 
Bioanalytical Chemistry, 405, 1641-1649, 
(2013) 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

[4] BANU, C., BULANCEA, M., IANIŢCHI, D., 
BĂRĂSCU, E., STOICA, A., Industria 
alimentară între adevăr şi fraudă, Ed. ASAB, 
Bucureşti, (2013)   

[5] KARTHEEK, M., SMITH, AA., MUTHU, 
A.K., MANAVALAN, R., Determination of 
adulterants in food: A review, Journal of 
Chemical and Pharmaceutical Research, 3, 
629-636, (2011) 

[6] MOORE, J. C., SPINK, J., LIPP, M., 
Development and application of a database of 
food ingredient fraud and economically 
motivated adulteration from 1980 to 2010, 
Journal of Food Science, 77, 118-126, (2012) 

[7] SANTOS, P. M., PEREIRA-FILHO, E.R., 
RODRIGUEZ-SAONA, L. E., Rapid 
detection and quantification of milk 
adulteration using infrared 
microscpectroscopy and chemometrics 
analysis, Food Chemistry, 138(1), 19-24, 
(2013)  

[8] OROIAN, M., Autentificarea produselor 
alimentare şi depistarea falsurilor, Ed. 
Performantica, Iaşi, (2014)