Pasteurization involves heating milk to between 63 °C and 72 °C for a few seconds before cooling it. The goal of this process is to destroy any bacteria that may be present during milking and that cause diseases such as salmonellosis.
Pasteurization destroys 100% of pathogenic bacteria, yeast and mould and 95% to 99% of other bacteria.
Although the sale of raw milk is prohibited in Canada, some people nevertheless believe in the virtues of this product, claiming that pasteurization destroys important vitamins and that drinking raw milk can prevent or treat allergies, cancer or lactose intolerance. But is this really true?
To find out, researchers in Ontario reviewed and analyzed 40 studies on the effects of pasteurization and the nutritional value of milk. The first finding: pasteurization has a small effect on the vitamins naturally found in milk. And contrary to raw milk, which only contains a small amount of vitamin D, pasteurized milk is fortified with this vitamin, which promotes calcium absorption and plays a key role in bone health. Only levels of riboflavin, or vitamin B2, decrease significantly during the pasteurization process. Nevertheless, pasteurized milk is still an important dietary source of this vitamin.
In terms of allergies, six studies have shown that unpasteurized milk has a protective effect. However, this relationship can also be explained by other factors related to a rural lifestyle and the farm environment and not just by the consumption of raw milk.
No study has shown a relationship between unpasteurized milk and cancer or lactose intolerance.
Overall, drinking pasteurized milk is still the safest way to enjoy milk.
Milk is an excellent source of vitamin D, an essential nutrient often called the “sunshine vitamin” since it’s also produced by our bodies when our skin is exposed to UV rays.
Natural sources of vitamin D
In addition to being produced by the skin through sun exposure, vitamin D is found in certain foods. However, there are only a few foods that are natural sources of vitamin D: certain fatty fish (sardines, herring, salmon, trout, mackerel), and egg yolk.
In Canada, milk is required to be fortified with vitamin D and is the main source of this micro-nutrient in our diets. Vitamin D can also be found in some fortified beverages and yogurts.
Studies show that people who consume milk more than once a day show a higher blood level of vitamin D than those who do so less than once a day. This is an excellent reason to enjoy milk every day!
According to Health Canada, the recommendations for vitamin D are 600 International Units (IU) for adults aged 19 to 70 years and 800 IU for people aged 71 and older.
The daily maintenance dose of vitamin D varies by age, but most children and adults generally require 600-2000 IU of vitamin D daily. For vitamin D-deficient children and adults, higher doses of vitamin D given either daily or weekly are recommended, followed by an increase in the daily dose of vitamin D
WHAT’S THE REAL DEAL ON LACTOSE INTOLERANCE?
Chances are that if you’ve been having tummy troubles you’ve been advised by friends, family or social media to avoid milk products because of the lactose. But when it comes to lactose intolerance, there’s a lot of misinformation buzzing about. Let’s clear up the confusion.
Does pasteurization destroy the nutritional properties of milk? Is it healthier to consume raw milk? Pasteurization has very little impact on the nutritional value of milk and is essential to preserve its safety.
In addition, all milk in Canada must be pasteurized and it is illegal to sell or buy raw milk.
Although farmers take necessary measures to ensure the safety of their milk, they cannot guarantee that it is bacteria-free until it is pasteurized. Pasteurization is important for human safety and is one of the most beneficial measures to protect the health of consumers. This process has been required by provincial law for decades and was added to the national Canadian Food and Drugs Act in 1991.
Pasteurization is the process of heating milk at temperatures high enough to kill potential pathogens that can cause disease. Pasteurization does not involve the use of any additives. This process not only makes milk safe to drink, it increases the shelf life (the amount of time a product can be kept before it spoils) because it destroys organisms that cause spoilage. There are three pasteurization methods:
- high temperature short time (HTST)
- ultra-high temperature (UHT)
In addition to being safe, pasteurized milk is also fortified with vitamin D contrary to raw milk which contains only very small amounts of this vitamin. Studies have shown that calcium absorption is unchanged with pasteurization and that vitamin A, vitamin D, riboflavin and niacin are not affected by heat. During the pasteurization process there is a minimal loss (approximately 10%) of thiamine and vitamin B12.2 But because losses are small in comparison to the large amounts of the B vitamins in milk, milk is still considered a source of these nutrients. About 20% of vitamin C is lost during pasteurization, but this loss is not nutritionally significant since milk is not an important source of vitamin C to begin with.
Some people have wondered about the effect of pasteurization on proteins and enzymes. While it is true that heating above 60°C can cause some proteins to break down, research has shown that heat-denatured milk proteins may even be more easily digested. Some people believe that raw milk is healthier and more digestible because it contains “live” enzymes that are deactivated by pasteurization. This is not true. Although some enzymes are denatured by pasteurization, the same thing occurs in the acidic environment of the stomach, and these enzymes are not required for digestion anyway.
Raw milk is unsafe because it can contain pathogens such as E. coli, salmonella, campylobacter, tuberculosis bacillus and listeria. Many people across Canada have become seriously ill after consuming raw milk.5 Symptoms of infection with pathogens potentially carried in raw milk can include headache, abdominal pain, diarrhea, fever, nausea and vomiting. There may be increased risk in people with weakened immune system, children, pregnant women and elderly people. It is for this reason that regulations have been put in place that make it illegal to sell or distribute raw milk in Canada.