The subject of raw milk and raw milk cheese has been a hot topic for as long as I have been making cheese. There are some very strong opinions (and often not a lot of facts) on both sides of the debate. It is symbolic of the divide that exists in many areas of our food production, namely the chasm of disconnect that often lies between the producer, the scientists and the consumers.
So why does the issue of raw versus pasteurised milk cheese get people’s backs up so much?
Possibly it is the tradition. But more than that, I think this debate goes to the core of the discontent much of society feels when our food gets manipulated. We feel like our autonomy is being threatened, our ability to live the life we choose, make our own decisions and be guided by our own common sense. We tolerate this in almost every aspect of our lives, but when it happens to our food, we seem to take it more as a personal attack.
Pasteurisation of milk is an excellent thing… when it is needed. For well over a century it has pre- vented diseases including tuberculosis, brucellosis, diphtheria, scarlet fever, and Q fever and has made milk a globally important source of food.
Pasteurisation is the name given to the heat treatment of milk (and other liquid foods such as juice, eggs and beer) to destroy pathogenic bacteria, which can cause illness. Pasteurisation does not sterilise the milk but it does destroy most of the good bacteria as well as all of the bad. The process temperature can vary and it is always in combination with a minimum time. The typical standard in the dairy industry is to process at 72°C (162°F) for 15 seconds. Pasteurisation (and refrigeration) is the reason milk now has a use-by date; some 2–3 weeks after it has left the farm. In contrast, UHT milk has been heated to a minimum of 138°C (280°F) for 2 seconds. This destroys all the bacteria in the milk, which is why it does not need to be refrigerated and has a ridiculous shelf life. It also denatures the proteins and caramelises the natural sugar in the milk, which is why it tastes so awful. Even when kept at less than 2°C (36°F) raw milk will start to deteriorate – it has a lifespan of 4–8 days because of the naturally occurring bacteria.