My wife and I made yogurt a few days ago. Making yogurt is quite easy, especially if you have a yogurt maker. All you need is milk, yogurt yeast, and some time. While it takes hours to make yogurt, most of that time the milk simply sits in the yogurt maker, warmed to a precise temperature, while the yeast grows like crazy and somehow converts the milk into yogurt.

Making yogurt reminded me of a passage from Warren Belasco’s Appetite for Change, which looks at how the counterculture of the 60s and 70s influenced the foods we eat today. Belasco points out that the counterculture subverted the dominant food beliefs of that time, beliefs that had been building since at least the early 20th century. During that time, the predominant belief was that food should be absolutely microbe-free, and that this could be accomplished by adding amounts of preservatives to foods.

As Belasco writes, “Inverting established notions of spoilage, the countercuisine equated preservatives with contamination and microbes with health…..brewer’s yeast, acidophilus milk, kefir, soy sauce, miso, tempeh.”

Yogurt, for example, is as far from microbe-free as you can get. It’s swimming with them, and that’s how you get from regular milk to yogurt. They work to turn the liquid milk into a jell-like solid. Bread, too, is filled with microbes—they’re what puff it up and make the little holes in a loaf of bread. Same with any sort of alcohol—microbes work hard to convert the juice they started with into alcohol (and don’t forget vinegar, which is just alcohol that went bad during the fermentation process).

This was Belasco’s point in his book: that at a time when the dominant idea coming from food companies was that everything should be microbe-free, the counterculture reminded us that, wait, there’s a set of foods that are good and valuable, and which are certainly not microbe-free. You can thank the counterculture for the popularity of yogurt, kefir, and lots of other foods like that.

The quote is from Appetite for Change, by Warren J. Belasco (Ithica, NY: Cornell University Press, 1989, 2nd updated edition), page 40.