Here at the OCC, we often get this question: I know very little about cheese but the fact that some cheesemakers use "raw" milk caught my attention. How do you ensure any bacteria is killed? - J.A.
We responded to J.A. and encourage them to find more traditionally cheesemaking practices reading our Hot Topics.
OCC - You're right, at first glance there does seem to be a conflict between raw milk cheese and the conventional approach to risk management in contemporary dairy food production-pasteurization. Bacteria are bad right? Shouldn't they be eradicated? Don't they make us sick?
The truth is, cheese, like any fermented food (wine, beer, bread, sauerkraut, etc), is a complex interaction between raw ingredients and the natural microbes in our ambient environment. It is the labor of microscopic bacteria that convert fluid milk into the healthy, safe, and preserved product known as cheese. In reality, very few bacteria are "bad," i.e. pathogenic, and the presence of "good" bacteria in cheese actually help ensure that the product remains safe to consume by outcompeting the undesirables (it's the principle of competitive exclusion, and while it's been known intuitively to traditional fermenters for a long time, contemporary science increasingly back it up).
Traditional cheesemaking, often referred to as milk's leap towards immortality, was a way of preserving fluid milk that in the millennia before refrigeration was prone to spoilage in just a few short days. The presence of good bacteria, and generally also salt and a low pH, allowed the highly nutritious but highly-perishable substance that is milk to be an important provision in many cultures months and even years after the cows, or goats, or sheep were milked. And in the form of traditional cheese, this is also a tasty provision.
Not only is raw-milk cheese (when thoughtfully made, according to established best-practices) safe to eat, it is delicious and nutritious. Natural bacteria in raw milk, and the other microflora present in dairy before heat-treatment, lend a great deal of the flavor to the final product that is all but eliminated when the milk is "cooked." What's more, there is an expanding body of literature that suggests that food rich in probiotics, i.e. cheese, yoghurt, and other fermented foods, are really quite nutritious, providing essential vitamins and minerals and potentially helpful with respect to allergies, asthma, and a host of other health concerns.