Do you love a mild mozzarella, a salty Parmesan or a funky brie? Thank microbes. 

Though the thousands of varieties of the world’s cheeses all begin as a white lump of curd, the diversity is astounding. From the flavor to the color to the texture, cheese goes from “uniform blandness to this cornucopia” thanks to bacteria, yeasts and molds. An article in Smithsonian Magazine – titled The Science Behind Your Cheese – shares the details.

“More than 100 different microbial species can easily be found in a single cheese type,” says Baltasar Mayo, a senior researcher at the Dairy Research Institute of Asturias in Spain. 

Scientists have only recently begun to study the microbial nature of cheese. To find out the bacteria and cheese present, scientists extract DNA from the cheese, then match it to genes in the database.

“The way we do that is sort of like microbial CSI, you know, when they go out to a crime scene investigation, but in this case we are looking at what microbes are there,” says Ben Wolfe, a microbial ecologist at Tufts University.

Though cheesemakers often add starter cultures of beneficial bacteria to fresh curds to transform it into a delicious cheese, Wolfe’s team found the microbiomes of the cheese “showed only a passing resemblance to those cultures. Often, more than half of the bacteria present were microbial ‘strangers’ that had not been in the starter culture,” continues the article. 

Those “strangers” dumbfounded researchers. Microbes like Brachybacterium found in Gruyère are more commonly found in soil, seawater and chicken litter. Or the Halomonas most commonly found in salt ponds and marine environments. Or, Brevibacterium linens found in damp areas of skin, such as between the toes. Those bacteria come from the environment of the cheesemaking facilities. The microbes come from the cow, goat or sheep, the bacteria in the farm’s stable, the skin bacteria from the hand of the milker, the microbes in the dairy storage tank and/or the sea salt in the brine used to wash down the cheese. Hundreds of bacteria have been detected in long-ripened cheeses.

“Furthermore, by repeatedly testing, scientists have observed that there can be a sequence of microbial settlements whose rise and fall can rival that of empires,” continues the article.

Modern cheesemaking is, sadly, more controlled, meaning modern cheese isn’t as flavorful. Cheesemaking has “become tamer over time,” cleaner and more sterilized, filtered, pasteurized, machine operated.

“Many of our cheddars, provolones and Camemberts, once wildly proliferating microbial meadows, have become more like manicured lawns. And because every microbe contributes its own signature mix of chemical compounds to a cheese, less diversity also means less flavor — a big loss.”

Read more (Smithsonian Magazine)