Food Adulteration continues to be a serious concern as non-authentic substances like dangerous coloring agents and preservatives are being added to the food products. Milk Products are largely affected due to this malpractice. FSS Act has provisions for penalty and prosecution but still number of cases are being reported everyday from many parts of India.
The Food Safety and Standards Authority of India has recently shared information on how the adulterants in Milk Products could be identified by using laboratory testing procedures.
Laboratory testing procedures for Milk products
To test if Vanaspati is present in sweet curd – Take one teaspoon full of curd in a test tube. Add 10 drops of Hydrochloric Acid and mix up the contents shaking the test tube gently. After 5 mins, examine the mixture. The Red coloration indicates the presence of Vanaspati in the curd.
To test if Blotting Paper is present in Rabri – Take a teaspoon of Rabri in a test tube. Add 3 ml of Hydrochloric acid and 3 ml of distilled water. Stir the content with a glass rod. Remove the rod and examine. Presence of fine fibres to the glass rod will indicate the presence of blotting paper in Rabri.
To test if Coal Tar Dyes available in Ghee, Cottage Cheese, Condensed Milk, Khoa, Milk Powder etc. - Add 5 ml of dilute Sulphuric Acid or concentrated Hydrochloric Acid to one teaspoon full of product sample in a test tube. Pink Color (in case of dilute Sulphuric Acid) or Crimson color (in case of concentrated Hydrochloric Acid) indicates presence of coal tar dyes. If Hydrochloric Acid does not give color, dilute it with water to get the color to see the result.
To test if Vanaspati or Margarine is present in Ghee – Take about one teaspoonful of melted sample of ghee with equal quantity of concentrated Hydrochloric acid in a test tube with stopper and to it a pinch of sugar. Shake for one minute and let it stand for five minutes. Appearance of crimson color in lower acid layer indicates the presence of Vanaspati or Margarine.