‍

‍

Modern-day supermarket milk is nothing like it used to be.

That's because, over decades, milk processors have invented processing techniques that make them more money, but ultimately change the milk and its taste.

In this post, I’ll explain three terms: pasteurisation, standardisation and homogenisation.

‍

Pasteurisation: Heating Milk

‍

Pasteurisation, named after Louis Pasteur, is essentially a heat treatment designed to kill bacteria. This process works by heating milk to specific temperatures for certain lengths of time. For instance, heating to 60 degrees Celsius for 30 minutes or 72 degrees Celsius for just 15 seconds can achieve pasteurisation. 

There are two main types of pasteurisation: batch and continuous flow. Batch is like heating a pot on a stove, while continuous flow sends milk through a heat exchanger for efficiency.

Continuous flow pasteurisation is energy-efficient but complicated to run and costly to set up. 

Batch pasteurisation takes a bit longer and uses lower temperatures. At Happy Cow Milk, we use the batch pasteurisation method.

An important point is, that pasteurisation doesn’t change the taste of the milk or the fat and protein content. But it does kill the bacteria in the milk.

The people who advocate for raw milk will also point out that pasteurisation affects the natural enzymes in the milk too.

This is correct; the test used to test pasteurisation is called the alkaline phosphatase test and this tests if the alkaline phosphatase enzyme is active or not. If it is deactivated, then the milk is deemed to be pasteurised.

Pasteurisation kills the good and the bad bacteria and it also deactivates the enzymes.

‍

Standardization: Keeping It Standard Consistency

‍

You might have heard that cream rises to the top of milk. This natural separation prompted the standardisation process. 

By law, whole milk must contain 3.2% fat, but cows produce 3.5% to 5% fat levels. In the old days to maintain a consistent fat content, milk factories used cream separators to separate the cream from the skim milk. They then reintroduced the cream to the skim milk until it was the desired fat content.

The factories would say we standardise milk because customers want a consistent product. That is true, but the real reason is that fat and protein are the valuable parts of milk. By standardising the milk, they can get an extra 10% more milk.

Modern-day standardisation uses the ultrafiltration method. Milk passes through a membrane filter, separating the solids from the skim milk. The difference is that the milk is separated at the molecular level. With a cream separator, the solids are the cream and the skim milk is left over.

With ultrafiltration, the solids are called retentate and the skim milk is called permeate.

With modern standardisation, the milk is deconstructed at the molecular level and then reconstituted.

‍

Homogenisation: Stopping the cream from rising

‍

The homogenisation process involves forcing milk through a microscopic hole under high pressure. This causes the fat globules to break into tiny particles and these very small particles stay suspended in the milk. The result is milk bottles will not develop a cream layer on the top.

The Happy Cow Milk Co Process

‍

At Happy Cow Milk Co we pasteurise our milk using the old batch pasteurisation method and we do not standardise or homogenise the milk.

Customers who tried Happy Cow Milk often notice a difference in taste and texture. Many people, even those who thought they were lactose intolerant, report that they can drink our milk.

I believe that these people are not lactose intolerant, they simply are not able to handle milk that has been subjected to all these processes.

We believe in less tempering with food. Whole unprocessed food is the best food and we use simple traditional methods. 

If you have any queries about milk, pasteurisation, or dairy farming, feel free to drop me an email at glen@happycowmilk.co.nz.

‍