Adulterated Milk

Roadside kadak chai stalls are always the center of attention in bustling cities, on railway platforms or close to offices. People relish road side tea during breaks to feel fresh. Not only roadside, tea has been part of our life since ages. Once it was used as a medicinal drink, although now it is popular as a recreational drink. The ritual of drinking tea has transcends boundaries, and roadsides are dotted with chai wallahs who serve the tea boiled up with spices, sugar and milk. But whatever we are savouring at these road side stalls, at home or even at cafes might slowly be poisoning us.
Many tea sellers and hawkers have confessed that they use adulterants like soap, acid, starch, table sugar and chemicals like formalin to prepare tea rather than using Milk. 68% of the milk in India is found to be adulterate as found in study conducted by Food and Safety and Standards Authority  of India (FSSAI). Unscrupulous milkman, dairies, or agents have taken to adulterating milk.

What are the adulterants?
Adulteration of milk reduces the quality of milk and makes it hazardous for consumption. Adulterants like soap, acid, starch, table sugar and chemicals like formalin or fevicryl are added to the milk. They increase the shelf life and volume of the milk.

• Table sugar: Lactose is a common sugar present in milk. Table sugar like sucrose is added to increase the carbohydrate content. This helps increase the density.
• Starch: Starch is another component that is added since milk contains large amounts of fat and addition of carbohydrates increases the solid content.
• Soap: Soap is added to increase foaming and make the milk thick.
• Acids: Acids are used as preservatives in food industry. It is added to increase the shelf life of milk.

Why is adulterated milk dangerous?

• Adulterants like Benzoic acid and Salicylic acid are linked to asthma problems and increased level of hyperactivity in children.
• It also causes Gastro-intestinal and kidney complications.
• It overburdens the kidneys and can even cause kidney failure.
• It causes liver damage as it is highly toxic

It can cause irritation in the gastrointestinal tract causing nausea, vomiting and diarrhea.

How can these adulterants be identified?

• Table sugar: The presence of table sugar in milk can be detected by adding ketose sugar. Ketose reacts with the resorcinol to give a red coloured precipitate, indicating the presence of table sugar.
• Starch: Iodine solution can be used to detect starch. Adding iodine solution to milk turns the solution to a blue black colour due to the formation of starch-iodine complex.
• Soap: Soap can be detected by adding a phenolphthalein indicator. The acidity of the milk neutralises the alkaline nature of the phenolphthalein solution and leaves behind a pink coloured solution.
• Acids: The presence of  acids can be detected by adding concentrated sulphuric acid and ferric (iron) chloride which reacts with benzoic acid and salicylic acid, and leaves behind buff and violet colored reaction products.