In large markets such as Delhi-NCR, daily milk consumption reaches 60-70 lakh litres (60,000-70,000 tons). Mother Dairy alone sells 3.5 million litres daily, most of it packaged milk.
A significant portion
of India’s population now consumes packaged milk, yet it remains common practice in households to boil packaged milk before consumption.
Is Boiling Packaged Milk Necessary?
Scientists, doctors, and dairy technologists generally advise against boiling packaged milk or pasteurised milk. Packaged milk is already treated through pasteurisation or ultra-high temperature (UHT) processing, making it germ-free and safe to drink. Boiling can actually reduce nutritional value, affecting vitamin B-complex, vitamin C, and milk proteins.
If packaged milk is fresh and properly stored after opening, it can be consumed directly.
Slight heating may be used if the milk has been left out of the refrigerator for several hours, but boiling is not required. In contrast, fresh homemade milk or milk from the milkman must be boiled, as it is unprocessed.
Types Of Packaged Milk
1. Pasteurised Milk
- Heated to 72-85°C for 15-30 seconds, then rapidly cooled.
- Destroys 99.9% of harmful bacteria like E. coli, Salmonella, and Listeria, while preserving beneficial nutrients and enzymes.
- Must be kept at 4°C; shelf life is 4-7 days.
2. Ultra-High Temperature (UHT) Milk
- Heated to 135-150°C for 2-5 seconds, then rapidly cooled.
- All harmful microorganisms and spores are destroyed.
- Sealed in aseptic packaging, protecting from air and light.
- Can be stored without refrigeration for 3 to 6 months if unopened.
Why Should You Not Boil Packaged Milk?
Boiling packaged milk can lead to nutritional and chemical changes.
Nutritional Changes
- Heat-sensitive vitamins (B1, B2, B6, B12, C) may reduce by 10-30%.
- Proteins may denature, reducing bioavailability.
- Beneficial enzymes like lactase and phosphatase are destroyed.
Chemical Reactions
- Lactose reacts with proteins, sometimes turning the milk light brown.
- Taste may change; the milk emulsion can break, forming a separate cream layer.
- Some calcium and phosphate compounds may settle at the bottom.
When Packaged Milk Should Be Heated
Packet milk should only be lightly heated in two situations:
- To drink it hot, or
- If the milk has been left at room temperature for several hours after opening.
Even then, heating to 70-80°C is sufficient. After opening, the milk should always be refrigerated and consumed within 2-3 days.
Why Raw Milk Must Be Boiled?
Milk from the milkman is completely unprocessed and may carry health risks:
- May contain harmful microorganisms, viruses, or parasites, posing a risk to children, pregnant women, the elderly, and immunocompromised individuals.
- The animal’s udder could be infected or have diseases.
- Milking, storage, or containers may be unsanitary, and milk may be adulterated with water or other substances.
Boiling raw milk at 100°C for 10-15 minutes:
- Kills all harmful microorganisms, including spores.
- Inactivates lipase enzyme, improving taste.
