The dairy industry follows many strict regulations from the government to ensure that the milk that we drink is safe.  One of the most common processes that milk undergoes to make sure it is safe is pasteurization.  Dairy products like milk, cheeses, and creamers must all be pasteurized to reach a grade A food standard. 

Raw Milk vs. Pasteurized Milk

Raw milk is milk coming directly from cows, goats, sheep and other animals. Pasteurized milk is dairy that is heated and cooled using a simple heating process to make it safe to drink.

What is Pasteurization?

Pasteurization is a process that involves heating food and beverages with high temperature for a very short period of time. This is done to destroy the pathogenic bacteria in the food without affecting its quality.

The process was introduced by Louis Pasteur around 150 years ago. Since the introduction of milk pasteurization at the beginning of the 20^th century, milk borne infections have dropped tremendously. Some diseases caused by bacteria like E. coli, Salmonella, Listeria and Campylobacter have almost been eradicated because of large-scale pasteurization. 

The Center for Disease Control and Prevention claimed 148 outbreaks were because of the consumption of raw milk.  Infants, children, elderly people and those who have weak immune systems are at higher risk of contracting serious illnesses from drinking raw milk. 

How is Milk Pasteurized?

There are three simple steps involved in pasteurization.

Step 1:

As the farmer milks the cow, the milk is first stored in a receiver jar. The milk is the transferred to a milk tank and is kept at a temperature of 4 ⁰ C. 

Step 2:

The chilled raw milk is placed in a pasteurizer where it is heated until it reaches 71⁰ C. 

The temperature is maintained for 15 seconds.

Step 3:

The milk is quickly cooled back to its original temperature of 4⁰ C.

The pasteurized milk can be bottled, or used for making dairy products like cheese, ice cream, butter and yogurt.

Frequently Asked Questions

Is pasteurization necessary for dairy products?

Raw milk may contain harmful bacteria that can make you very sick. Drinking unpasteurized milk may lead to fever, vomiting, diarrhea, and in worst cases, death.  Children, pregnant women and the elderly are more at risk of getting sick from raw milk. 

Production and processing standards for dairy requires the use of pasteurized milk for dairy products to ensure consumer safety.  You can use raw milk for your cheese, ice cream or butter for home use; but if you’re planning to sell your products, food standards need to be followed.

Does pasteurization change the taste of milk?

Blind raw milk taste tests reveal that there isn’t much difference between the taste of raw and pasteurized milk.  Raw milk only tends to be thinner than pasteurized milk.

Does pasteurization destroy the nutrients in milk?

Studies show that pasteurization does not significantly change the nutritional value of milk. Raw milk contains a miniscule amount of vitamin C that does not survive the pasteurization process; however, the important nutrients in milk are not affected by the process.  Pasteurized milk is still an excellent source of calcium, protein, vitamins A and B12, thiamine and riboflavin. Most milk producers also fortify pasteurized milk with vitamin D.

Can you get food poisoning from pasteurized milk?

Since pasteurization kills the disease-causing bacteria in raw milk, being food poisoned from pasteurized milk is very unlikely. Correct handling of milk-bottling, sealing and refrigeration after opening, are still necessary to prevent milk contamination.

What is the shelf life of pasteurized milk?

Though pasteurization kills most disease-causing bacteria, there are few types of harmless bacteria that survive pasteurization.  Once the milk is opened, it is best to refrigerate it and consume it within seven days.  Past this period, there is a high chance of milk spoiling.

What do I use to pasteurize milk?

If you are pasteurizing milk at home for personal consumption, you can use a double boiler and a thermometer.  For large-scale milk production, a pasteurizer and a milk cooling tank are the most essential equipment.