Benevolent Bacteria: A fermentation revivalist’s perspective on the bio-value of cheese
Artisan cheesemaking was an early herald of today’s emerging fermentation revival. Raw-milk cheeses in particular are especially delicious, and also supportive of good health, precisely because of the biological complexity that they embody.
Even though bacteria produce sublime delicacies and we need them to live, we have been taught to fear and to kill them. This bias is reflected in regulatory frameworks that assume that bacteria beyond specific strains chosen for utilitarian purposes pose a danger. Raw-milk cheesemakers—along with wild-yeast brewers; sauerkraut, salami, and kombucha makers; sourdough bakers; and other fermenters—value and celebrate microbial biodiversity. These artisans and do-it-yourselfers are feeding live-culture probiotic delicacies to a population literally starving for bacterial stimulation.
Bacteria are the context for all life. All animals, plants, and fungi are believed to have descended from bacteria, and no other form of life has ever existed apart from them. In our bodies our cells are outnumbered ten to one by the bacteria we are host to. We could not digest food, reproduce, or survive without them. Certain bacteria that people ingest for perceived health benefit are called probiotics. The term “probiotic” contrasts with all the chemicals in our lives—drugs, cleansing products, and even the chlorine in water—that are antibiotic.
Probiotics are most often marketed in the form of capsules or as supplemental ingredients in “functional” foods. In this context probiotics are specific strains, often proprietary, some of which have been tested in clinical trials. But diverse foods with indigenous or introduced bacterial populations cheeses included—are also probiotic, because the live bacteria in them also contribute to good health. Beyond any specific strain, research has shown that a diet rich in bacterially diverse live-culture foods improves immune function. Cheeses are rich sources of microbial diversity. All forms of life, including the animals we milk, are host to elaborate microbial ecologies of bacteria and fungi. Microbial ecologies exist everywhere on Earth, including the environments in which we age cheeses. The organisms spontaneously present in milk itself (when milk is raw), those we add to it, and those present in aging environments—along with how we manipulate the milk via temperature, humidity, time, agitation, straining, pressing, kneading, molding into forms, and so on—determine what type of cheese milk becomes. Each cheese, with its particular mix of organisms, reflects the specificity of place.
Some of these organisms, and the accumulation of the acids that are their metabolic by-products, make cheeses stable for long-term storage; others create distinctive textures, as in runny cheeses; others result in edgy flavors that are beloved by some and reviled by others. Cheeses (like all other fermented foods and beverages) have until recently all been products of communities of organisms, never single species. In the natural world all organisms exist in communities. In cheesemaking and other fermentation arts, these communities came to be perpetuated primarily by introducing a bit of the previous batch into the next, a practice known as “backslopping.”
In the age of microbiology, many different selected microbial cultures have been isolated and propagated, and any cheese may be made anywhere, with the right culture and simulated environmental conditions. Unfortunately, the widespread use of a limited number of commercial cultures is diminishing the microbial diversity of cheeses. Rather than working with the milk and the environment as they exist in different places, which gave rise to so many novel and distinctive cheeses, the cheesemaking industry, along with many artisan and home cheesemakers, relies on selected cultures that have been isolated and propagated in laboratories.
The use of these cultures may result in greater predictability and product consistency, and certainly can produce many fine cheeses, but it’s at a cost: “The biodiversity of indigenous microbial populations which developed in concert with each region’s cheese is at risk,” warns cheesemaker and microbiologist R. M. Noella Marcellino. Cheese is a great delicacy indeed; yet it is so much more. Cheese is the embodiment of ecosystems and biodiversity. Each raw-milk cheesemaker preserves or rebuilds biodiversity.
Sandor Ellix Katz is a “cultural revivalist committed to the spread of fermentation fervor.” He is the author of the website wildfermentation.com as well as several books on the subject, including the newly published The Art of Fermentation (Chelsea Green)