Frauds in the sale of Milk


  • The adulteration of milk is very common in India. There are various chemical tests to detect these adulterations. (eg) Addition of water to milk – detected by

    • Determination of specific gravity of milk by lactometer.
    • Test for nitrate in milk: Normal milk does not contain nitrates but ordinary water does. The presence of nitrates in the milk is a sure test of adulteration of milk with water.

Routine methods in the adulteration of milk



Reduction of fat

  • By adding water
  • By skimming of milk
  • By skimming and watering

Addition of thickening agents

  • This is done to increase the specific gravity and consistency of the milk.
  • It is done by adding starch gelatin and cane sugar

Addition of colouring agent

  • Sometimes colours are added to make milk more attractive
  • The colours generally used are annatto and coal tar dyes.

Addition of preservatives

  • Preservatives like formalin, boric acid, hydrogen peroxide, sodium bicarbonate, sodium carenate are added to retard the decomposition with an objective to
  • Delay the curdling of milk
  • Destroy the pathogenic bacteria

Accidental adulteration

  • Some adulterants are mixed accidentally in the milk
  • (eg) urine or animal, dung, vegetable cells, dirty water.
  • These agents give a foul smell.

Last modified: Tuesday, 5 June 2012, 12:37 PM