All About Pasteurization
Pasteurization has very little impact on the nutritional value of milk, and could even have benefits on health.
The pasteurization process involves heating milk to very high temperatures and then suddenly cooling it down in order to destroy disease-causing bacteria. This process is mandatory for all the milk sold in Canada not only to ensure the safety of milk but also to increase its shelf life.
Studies have shown that pasteurization has no effect on calcium absorption and that vitamins A and D, riboflavin (B2) and niacin (B3) are not affected by heat. Pasteurization does produce a slight loss in thiamine (B1) and vitamin B12, although milk is still a source of these two nutrients. Pasteurized milk is also fortified with vitamin D, contrary to raw milk, which contains only very small amounts of this vitamin.
Raw milk is permitted for use in cheesemaking for cheeses that are aged a minimum of 60 days. This is because the way raw milk cheeses are manufactured and produced helps eliminate any harmful bacteria that may be present in raw milk.