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Pasteurization inhibits good bacteria

Pasteurization is one of the culprits in killing off the beneficial microbes we need in our guts to keep us healthy.

Following the E. coli death and illnesses from cheese made in Salmon Arm, the Canadian Food Inspection Agency recalled all types of cheese from the responsible facility.

Raw-milk cheeses immediately came under widespread suspicion. The CFIA has long been at war with raw-milk production, holding that only pasteurised milk (milk which has been heated for sterilization) is safe.

It has been known for some time that excessive hygiene can cause more trouble than it prevents and I had a vague notion that obsession with killing germs creates more vulnerability. Something to do with not building up natural immunities.

But I’ve been reading Michael Pollan’s latest book Cooked, in which he investigates the advantage that humans derived from cooking our food.

When we no longer had to spend hours finding and digesting meats and plants, we saved energy and time and our brains grew bigger.

Pollan divides his research into four types of cooking and poetically calls his categories air, fire, earth and water, which the Ancient Greeks believed were the universal elements.

The food he investigates for the earth category is cheese.

And that’s where I learned about the pasteurizing and post-pasteurizing debate.

Long before pasteurization, cheese was known as a nutritious food made mostly from the milk of cows but also other mammals.

Around 4,000 years ago people started to breed animals and process their milk into cheese.

And what a variety of wonderful cheeses were developed.

I miss Scottish crowdie, a delicious, crumbly, spreadable low fat “country” cheese, wonderful with French bread.

My brother acquired a taste for Limberger cheese, which my mother claimed smelled so awful that she threatened to make him keep it under his bed with his smelly socks.

The post pasteurizing arguments are very compelling. Top of my list is that the great classic cheeses are made with raw milk.

But it’s also very important to know that pasteurization is one of the culprits in killing off the beneficial microbes we need in our guts to keep us healthy.

Like the killing of the bees by the neonicitinoid pesticides, we have created bigger problems that the ones we fixed.

Also persuasive is the statement by an English milk expert that, “cheese is rarely involved in outbreaks of food poisoning,” and that “the most frequent causative factor in cheese-related outbreaks is post-production contamination” – i.e. after pasteurizing.

Pollan tells how a California maker of cheese from an old French recipe, threatened with closure by the food police, set up a demonstration using two batches of cheese, one in her old wooden barrel and one in a stainless steel vat.

She inoculated both with E. coli. The cheese made in stainless steel had high levels of the bacteria.

The cheese from the wooden barrel had almost none.

There were good bacteria encouraged by the traditional wood but none to help the cheese made in the sterile container. There is magic in traditional methods. The health inspector backed off.

Marjorie Stewart is board chairwoman of the Nanaimo Foodshare Society. E-mail marjorieandalstewart@shaw.ca.