Associate Professor

Deptt. of Dairy Sc. & Tech. (Formerly A.H & Dairying )

R.K. (P.G.) College

 Shamli, U.P., India 

Adulteration in general may be define as any change in the natural level of milk Constituents. These may be brought about the addition and/or subtraction of some of the legally prohibited foreign substances to genuine milk or by removing some Valuable Constituents (like fat) with the view to increase the bulk or quantity and to make extra profit.

“Any substance or material is admixed in the pure milk which deminise  the nutritional significance of the milk along with Injurious to the human healthier issues is known as adulteration of milk "

Adulterants

It is materials which act as a contaminant when Combined with other materials. These adulterants make the milk, unsafe for human consumption or substandard or misbranded.

Type Of Adulteration

Adulterants that have been used ser the adulteration of milk may be classified into the following two categories.

1.     Intentional adulteration

It is done deliberately with. Knowledge for financial gain or to earn more margin of profit. In these category some of Neutral major adulterants are water. Skim milk S.M.P. Starch Preservatives detergents, neutralizers blotting Papers, colouring matter, mud, sand, marble, chips chalk, powder, stones etc.

2.     Incidental

Its occurs accidentally in natures without yours knowledge, ignorance or lack of proper facilities. under this category adulterants are Pesticides residues, larval in foods, dropping of rodents etc.

Adulteration takes place at all the three stages- Milk Producers, Distributers and retailers.

Causes of Adulteration

The practice of adulteration in milk has become very easy and common under the existing Conditions of handling of milk. The causes are numerous and can be outlined as follows:

1.     Physical nature of milk.

2.     Short supply in the market due to high demand with low Production.

3.     Low minimum legal standard and by and their improper implication

4.      Lack of knowledge and awareness in tour of human healthier issues.

5.     Bad intention - Seller cheat the consumer to gain financial extra profits.

6.     Spoiled socio-economic status.

7.     Degraded moral human society.

8.     Low buying powers of the consumer.

9.     Unorganized Conditions of  Indian dairy sector.

10.      No fear year of punishment in the whole sale Contractor retailers, vendors, Hallwais, milk producers etc.

11.      Competition for capturing more market.

12.      Buffalo's milk sold as cow milk.

Effect of Adulterants on Properties and Chemical Composition of Milk

Nature of adulterations in milk	Effect ion
	Lactometers Reading	Fat %	S.N.F %
1.Additon of water	Lower	Lower	Lower
2.additon of skim milk	Higher	Lower	Higher
3.Additon of skim milk  + water	Normal	Lower	Normal
4.Removal of fat (cream)	Higher	Lower	Higher
5.Removal of fat and addition of water	Normal	Lower	Normal
6.Additon of water starch	Normal	Lower	Normal
7.Removal of cream and addition of starch	Higher	Lower	Higher
8.Addition water and urea	Normal	Lower	Normal

Airthematic Calculations

The arithmetic calculation introduced in this chapter is divided into two parts.

1.     Adulteration Of Milk

2.     Reconstitution Of Milk

Adulteration & Milk

Normally genuine milk is adulterated by creamery and milk vendors with water or skim milk of both when milk is sold in the form of raw and loose to the consumer occasionally cream may be removed from higher fat milk. Due to definite relationship between fat and solids not-fat in milk, mature of adulteration can easily be detected. To determine the nature and extent of adulteration of milk, fat percentage and Lactometer Reading (L.R.) are taken into consideration. Addition of water only reduces the fat% To and L. R in same ratio while adding. skim milk reduce fat% and rise L.R. so ratio become disturbed Adulteration in milk may easily be detected by using these Principle. Extent of adulteration (II Step) Can be calculated by using the Pearson's square method.

Problem-1

250kg of genuine milk sample ( containing 6%, fat and 30’ C.L.R has been adulterated to contain 3% and 15 C.L.R. determine the nature and extent of adulteration done in this, genuine  milk sample.

Solution

Step-1

Nature of Adulteration.

Test done             genuine milk         Adulterated milk             Difference                         Proportion                   

Fat                               6.0                    3.0                                3.0                                3/6=1/2

CLR                              30                     15                                 15                                 15/30=1/2

 

Decrease in the percentage of fat is proportionate to the decrease in Correct Lactometer Reading (CLR), therefore, milk has been adulterated with water only. As water contain  0% fat and 0% C.L.R.

Step-2 Extent of Adulteration.

It can be determined by using the Pearson's square method as follows: 

                                

 

Percentage of water in the adulterated milk-

∵ 6kg adulterated milk Contain =3 kg of water

∴ 100kg  of adulterated milk contain= 3/6x100=300/6=50%

Percentage of adulteration =3.0/3.0x100=100%

Result – Amount of water added to milk  350kg

            Amount of adulterated milk =350 +350 = 700kg

            % of water added to milk = 50%

            % of adulteration  = 100 %

 

Problem 2 - 500kg of genuine milk testing 7.0%. fat and 31 CLR has been adulterated to test 45 % fat 28 C.LR. Determine the nature and extent of adulteration done in this genuine milk

Step-1.Nature of Adulteration

Tests done             Genuine Milk                 Adulterated Milk                       Difference              Proportion

Fat                            7.0                                   4.5                                            2.5                    2.5/7.0

C.L.R                         31                                    28                                             3                      3/31

 

The decrease in the percentage of fat is not proportionate to the decrease en C.LR, therefore genuine milk has been adulterated with water and separated milk. The mixture  (water+ separated milk) has no fat.

Step-2 Extent of Adulteration –

Amount of water and separated Milk =277. 77/kg

Amount of adulterated Milk 500+277.77 =777-777 kg

Suppose the amount of Sept. Milk = M kg.

Then amount of water  = (277.77-M) kg

Equation

Amount of adulterated milk (kg) x C.L.R = Amount of (genuine milk (kg) x C.L.R. + Amount of Sep.Milk x C.L.R+

   Amount of water (kg) x C.L.R

=777.77 x 28 = 500 x 31 + M x 40 +(277.77-M) x 0

 Since CLR of M is  40 and CLR water is  0

21777.56 = 15500 +40M  + 0

- 40M= - 21777.56+15500

- 40M= - 6277.56

Amount of Sept. Milk M = 6277.56/40 - 156.939

Amount of water = (277·17-M)

Amount of water = 277.77-156.939 = 120.831

Result

Water added = 120.831.kg         =120.831/777.77 x100= 15.535%

Sept. Milk added=156,939 kg    =156.939/477.77 x 100= 20.178%

 Genuine Milk = 500.000 kg        =500/777.77× 100 = 64.286%

Adulterated  Milk = 777.77kg      =100%

 

Problems : 3   A sample of milk collected from a mitt vendor and tested 3.0 fat and 25 CLR when the genuine milk from milk producer was tested it contained 6.5% fat and 32 LR Examine the mature and extent & adulteration done in the genuine milk sample.

Solution

Step 1 -  Nature of Adulteration.

Tests done       Genuine Milk                                            Adulterated Milk           Difference              Proportion

                       Collected from milk                                  Collected from milk

                         produces                                                      vendor

Fat                         6.5                                                              3.0                            3.5                        3.5/6.5

C.L.R                      32                                                               25                             7.0                        7/32

 

The decrease in the percentage of fat is not proportionate to the decrease in CLR, therefore, genuine milk has been adulterated with; water and separated milk. The mixture of water + separated Milk has zero fat.

Step 2 Extent of Adulteration- C.L.R of Sept. Milk = 40, C.L.R of water = 0

Suppose amount of adulterated milk = 100 kg

Amount 6.5% fat genuine x = 300/6.5 = 46.15 kg or 46.15%

so Amount of sept. Milk + water = 100- 46.15=53.85 kg or 53.85 %

 Let amount of Sept.Milk = S kg

Amount of water  = ( 53.85 – S ) Kg

Equation

Amount of Adulterated Milk X CLR  =( Amount  of Genuine milk X CLR  + Amount of  sept. Milk X CLR  + Amount of water ) X CLR 

100x25 = 46.15X32+Sx40 +(53.85-S) X 0

2500 = 1476.80 + 405+0

- 40S =- 2500+1476.80

-40S=-1023.20

Amount of Sept. Milk (S)=1023.20/40  = 25:58 or  25.58%

           Amount of  water = (53.85-S)

          Amount of  water =  53.85-25.58 =28.27kg  or 28.27%

 

 

 

Result - Amount of Genuine Milk = 46.15 kg or 46.15%

Amount of Sept. Milk = 25.58kg or 25.58%.

Amount of water = 28.27kg or 28.27%

Amount of Adulterated Milk = 100.00 kg. or 100%

 

Problem. 4  200 kg genuine Milk Continued 6%. fat and 30 C.L.R has been adulterated to contain 4% fat using skim milk of 0.05. fat and 39 CLR. Determine the amount of Skim milk utilized and CLR of adulterated milk.

Solution

Step 1

                 

Amount of Skim milk (S) =  400/3.95 = 101.265 Kg

Amount  of adulterated Milk = 200+ 101.265

                                       = 301.265 Kg

Step 2

Equation

Amount Adulterated Milk X  C.L.R = Amount of genuine Milk X C.L.R + Amount  of skim milk X C.L.R

301.265 X C.L.R = 200×30 +101.265×39

301.265 X C.L.R = 6000 +3949.33

C.L.R = 9949:33/301.265 =33.02

Result - Amount of skim Milk = 101.265 kg.

C.L.R  of adulterated Milk = 33.02

Problem-5 A sample of pure cow milk, on analyses, was found to have -0.52°C as  its  freezing point. Determine the percentage g water admixed to the cow milk

Solution:-

water added %= 100 (F-F₁)/F

Where

F = Freezers point of the pure cow milk   = - 0.55°C

F = Freezers  point of the adulterated milk

Water added %  = 100x [-0.55-(-0.52)] / - 0.55

100 x (-0.03) / - 0.55

- 30 / -0.55

Result - water added = 5.45%

Reconstitution of Mills

Reconstituted / Rehydrated milk may be prepared either from Skim milk powder (S.M.P) or whole milk powder (WMP) by the addition of water, The Fat and SNF ratio is adjusted equal to that of fresh pure skim milk or fresh pure whole milk. Due to poor wettability, whole milk Powder (W.M.P) possesses problems in reconstitution hence, reconstitution should be done with Care. Usually SMP is used since it is more soluble in water and produces les sediments.

The arithmetic calculations related to this are as follows.

Problem-1

Find out the amount of Skim Milk Powder (SMP) having 0.1% fat and 96% solids not fat (S.NF) required to make, reconstituted Skim milk containing  8.80% S.NF. Also calculate % of fat in reconstituted milk

Solution

S.N.F required in 100kg reconstituted  Milk = 8.80Kg

SMP required = 100/96 X 8.80  = 9.12 Kg

water required = 100-9.12 kg = 90.88kg

Fat%  in Reconstituted milk = 9:12×0.1/100 = 0.009%

Result- SMP required = 9.12 Kg

Fat % in reconstituted  milk = 0.009

Problem 2

Find out the amount of whole Milk Powder (WMP) having 39 fat and 57% S.NF required to & make 7000 kg of reconstituted whole milk containing  6% fat.

Solution:

Amount of fat required for reconstituted while milk - 7000 x6/100 =  4200/100 = 420 Kg.

Amount of WMP required to supply 420 Kg fat =100x420/39 = 1076.92 kg

Amount & water required = 7000 - 1076.92 kg = 5923.08kg

Amount  of S.NF supplied through WMP = 1076.92 X 57/100 = 61384.44/100 = 613.84 kg

S.NF% in Reconstituted whole milk  = 613.84/7000 X 100 = 8.769%

Result - Amount & WMP required = 1076,92Kg

Water of water required = 5923.8 Kg

Amount of Reconstituted Milk  = 7000 kg

Reference

1.     Bhati, SS and Lavania, G.S. (2000) Dany Science V. K Prakashan Baraut.

2.     Shukla S.G. (2013) - MILK & MILK Processing, Aman Publishing House Meerut 1^st  Edition.

3.     Sharma, Aditi, Singh, Swati and Tanwar kumud - (2020). Present status of Adulteration in milk in jaipur International Journal for innovative Research in Multidisciplinary Field Vol. 6 issue-11 NOV-2020

4.     Hari Singh (1998) Dairy Science and Dairy Mgt. & Tech, Saroj Prakashan 647, katra, Allahabad.

5.     Jahur I. J. & GUPTA RAMJI – Milk, Milk Processing and human Nutrition Rama Publishing House, Meerut

6.     Jai Singh (19070)) Dairying, Nidhi Prakashan Baraut.