Pasteurisation of Milk: A Boon or Curse?

Science and technology is undoubtedly escalating its claws in every area of nature, and inventions are being made towards advancement of civilization. The world today is not the same as it was decades ago, credit goes to technology growth. Nature has given us myriads of gifts, and technology has made variations in them, apparently for our benefits. But, I am not sure whether use of technology is always beneficial for mankind. Let us take the case of pasteurisation of milk. There is a big controversy in the West, whether pasteurisation of milk is beneficial or detrimental to human health. Proponents of the process argue that it is to make milk and milk products safe for consumption by razing away injurious bacteria, and to improve keeping quality of raw milk.


Let us briefly know what pasteurisation is. It is an artificial process used to destroy dangerous bacteria without substantially changing the composition or flavour of milk. The method also prevents rapid souring of milk. Under this process milk is heated to a temperature between 55 and 70 degrees Celsius for 30 minutes, and then is rapidly cooled and stored at a temperature below 10 degrees Celsius. Sometimes higher temperatures are applied for a shorter period of time. The temperatures and time are determined by factors necessary to destroy bacteria (pathogens). The process was named after the French chemist Louis Pasteur. Pasteurisation has been used to kill bacteria in milk including Salmonella, Listeria, Campylobacter, E.coli, and Bracella. The problem is that in addition to the killing of bad bacteria, pasteurisation kills good bacteria too. However, researches have been conducted and have proved that pasteurisation diminishes the nutritional value of raw milk that is requisite for human health.


Some of the effects of pasteurisation are: the process destroys the enzyme phosphate present in raw milk. Phosphate is required to split and assimilate mineral salts in foods that are in the form of Phytates. Protein, a valuable nutrient in raw milk, is greatly affected by the process. Its digestibility is reduced by 4% and biological value is reduced by 17%. The effect of the process on vitamins, vital nutrients in raw milk, is that the pasteurisation process destroys about 38% of vitamin B complex; and vitamin C is weakened or destroyed. Studies show that infants who are fed with pasteurised milk might develop scurvy. Not only protein and vitamins, but also mineral contents in raw milk are badly ruined by the process. After the process the calcium content is very much diminished. The loss of soluble calcium in regards to infant’s growth and development is a very important factor. It is not only the concern in children regarding bone formation and teeth, but also in adults about the calcium content in the blood. It also destroys 20% percent of iodine present in raw milk and causes constipation.


After lot of research it is apparently clear that the process of pasteurisation deteriorates quality of raw milk. Raw milk is in demand and is desirable by people who are becoming aware about the dangers of pasteurisation to a product of daily consumption. Despite such scientific evidence in favour of raw milk and against pasteurised milk, and the fact that human beings have always lived on raw milk without facing any serious threats to life, an intriguing fact is that sale of raw milk has been made illegal in the US except in a few states. People can only get pasteurised milk or organic milk. Organic milk is the milk that comes from the cows that are raised on organic food, no growth hormones or antibiotics are used and cattle graze on grass which hasn’t been sprayed with pesticides. However, organic milk is around two and a half times the price of pasteurised milk, which becomes difficult for everyone to afford.


However, milk is such an important component in daily life, that despite so much of controversy about pasteurisation and no good alternative for raw milk, people don’t have choices but to have pasteurised milk in the US. The problem is not of the West anymore, but is rapidly transferring to countries like India too. This is the issue created by technology and need to be raised in India before pasteurised milk becomes the choice of the government of India.


Deepti Vithal

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