“I’m curious about raw-milk cheese. I don’t understand how it can be sold legitimately in the United States when, in many states, fresh raw milk can’t be. And is it really better than pasteurized cheese?”

—Erica Olsen

Milk destined for the cheese vat comes from cows, sheep, goats, or, less commonly, water buffalo. That milk can be raw (that is, straight from the teat) or pasteurized. Raw milk is teeming with microorganisms both friendly and harmful, and the latter are the reason why pasteurizing is a dairy-industry norm. Since 1950, all cheeses sold in the United States, whether domestic or imported, must be made with pasteurized milk or, if made with raw milk, aged at least 60 days at a temperature no less than 35°F to allow pathogens such as Listeria, E. coli, or salmonella, if present, to die off to levels below the infectious dose. The heat-treatment procedure known as thermization (or thermalization) is not a type of pasteurization. Although it reduces bacterial counts, it doesn’t reach the temperature necessary to kill Listeria, so cheeses made with thermized milk must also be aged at least 60 days.

It sounds so simple, doesn’t it? Readers interested in the Byzantine workings of government policy (and the law of unintended consequences) can find a historical time line of key studies and U.S. regulatory changes for raw-milk cheeses published in September 2013 on the Marler Blog, an important chronicle of food-borne illness. And in a 2011 interview in Culture magazine, University of Vermont microbiologist and international Listeria authority Catherine Donnelly stressed that cheese has a very, very good track record for safety—but also elaborated on why Listeria in particular is of such concern. The bacterium isn’t responsible for as many cases of food-borne illness as salmonella, but it causes a much higher percentage of deaths.

“It can exist invisibly in creamery environments—in drains, on floors, or attached to stainless-steel surfaces,” she said, noting that it can also grow in a wide temperature range. “But even if someone is making cheese with pasteurized milk, that’s not necessarily a safeguard, because the source of Listeria is most often in the cheese-making environment, not in the milk.” In other words, the romantic, bucolic image we all have of how farmstead cheeses are traditionally crafted is a myth. Every cheese-making operation I’ve seen in the past 10 years or so is as fanatically clean as an operating room.

Although pasteurization and strict hygienic practices stop Listeria in its tracks, what Donnelly had to say about the Food and Drug Administration’s 60-day aging regulation may surprise you.

“The 60-day aging rule was really intended to be applied to cheeses that as they age become hostile to microbial pathogens—like cheddar and hard-ripened ones. Now, with all the artisan cheese being produced in the United States, cheese makers must apply the 60-day rule to such cheeses as soft-ripened cheeses that were never designed to use aging to achieve safety,” she said. “So in a Camembert, for example, holding that cheese for 60 days actually increases its health risk substantially. If you think about France, where they sell Camembert or Brie at 30 days, there’s a much lower risk of Listeria contamination and growth in their soft-ripened cheese. In fact, in France you can’t even sell an AOC Camembert beyond 59 days because the risk is considered to be so great. So even though the FDA applies the 60-day rule to raw-milk soft-ripened cheeses, our research indicates that it’s not good practice to enforce that. The agency is, however, in the process of doing a soft-cheese reassessment.”

I emailed Donnelly the other day for an update, and she answered with alacrity. “The FDA did publish results of its quantitative soft cheese risk assessment,” she wrote. “Their data shows that testing every lot of raw-milk cheese for Listeria decreases Listeria risk below use of pasteurization of milk for cheese manufacture. Thus, it shows that cheese makers can achieve an equivalent level of safety for raw-milk cheeses by incorporating testing.” Which is not a cheap fix, as testing at a private dairy lab can run to hundreds of dollars a month.

“Of greater concern to cheesemakers currently is the FDA’s implementation of stringent standards for non-toxigenic E. coli in cheeses,” Donnelly continued. “The standards are so rigorous that it is difficult to achieve the standards when making raw-milk cheeses. It should be noted that Europe only tests cheeses made from pasteurized milk for E. coli as a hygienic index. They understand that presence of E. coli in a raw-milk cheese is not a meaningful food safety standard.”

We’ve all been conditioned to recoil at the very thought of E.coli, but non-toxigenic E. coli does not make people ill, and the standards, if implemented to their full extent, would have a devastating impact on the production (often on a rescued derelict farm) and consumption of raw-milk cheeses, both imported and domestic—as well as on local economies, and indeed, the future of agriculture in states such as Vermont, which has welcomed back-to-the-land types for generations.

Jeff Roberts, cofounder of the Vermont Institute for Artisan Cheese, obligingly dug up some data for me. “On a national level, in 2006, I identified 97 out of 402 licensed producers doing raw-milk cheeses, and another 84 doing both raw-milk and pasteurized,” he said in a phone conversation late last week. “In 2012, I identified 818 nationwide; raw-milk producers numbered 172, and those doing both numbered 156. That’s a 77 percent increase in raw-milk producers, and an 86 percent in those doing both.”

The powerful allure of raw-milk cheeses derives primarily from the fact that their enzymes haven’t been destroyed by pasteurization (the same is true of cheeses made from thermized milk). I dove into the subject of raw milk in fluid form last August, and in a follow-up column made the point that the only humans who can put bovine enzymes to good use are cheese makers, who say they add an ineffable richness and complexity of flavor to the finished product.

“Enzymes are responsible for the breakdown of fats and proteins in aging cheese, a breakdown that creates the flavors and aromas that determine the cheese’s very character,” wrote Rob Kaufelt, owner of Murray’s Cheese, the oldest cheese shop in New York City, in The Murray’s Cheese Handbook. “Inhibited enzymes mean diminished flavor and stunted aroma. This is why pasteurized cheese is often considered to be blander, and generally less tasty, than raw-milk cheese.”

Don’t skip over the words “often considered” in that last sentence. There are any number of world-class pasteurized cheeses (including the wantonly runny Stinking Bishop), and Kaufelt’s book gives them their due, as does Roberts’ landmark Atlas of American Artisan Cheese.

“The questions around food safety are very real ones,” said Roberts. “In this country, cheese makers have been working with pasteurized milk for 65 years. The fact that a cheese is pasteurized doesn’t mean that it can’t be an outstanding product. The Cowgirl Creamery is a great example. All their cheeses are pasteurized, but their milk is organic and unique because of where the cows graze, in Point Reyes. Their Red Hawk, a triple crème, took Best in Show at the American Cheese Society in 2003. It can only be made at Point Reyes—whatever is in the air there makes that cheese come alive.”

Enter the French concept of terroir—the idea that a product such as wine or cheese is not just the sum of its ingredients but that it contains the essence of place, land, and method. But American cheese makers, with their entrepreneurial, individualistic bent, have a very different mind-set from that of their counterparts in Europe.

For Europeans, terroir stretches back centuries, and their great cheeses are standardized in a way that Americans find difficult to understand. The European Union doesn’t have an aging rule, but hygiene regulations and food-safety practices for milk, animals, and workers are strict, and cheeses made from raw milk must be labeled as such. (I know! What a concept.) And that’s just for starters. Certification systems such as France’s Appellation d’origine contrôlée (“controlled designation of origin”) dictate what breed of animal a producer must raise and the exact percentages of what it can and cannot eat in order to sell a Roquefort, Camembert de Normandie, or Gruyére, for example.

A rising tide floats all cheeses. “While the strong U.S. dollar of the 1990s spurred American consumption of European cheeses, the strong euro of the 2000s helped to widen the market for domestic cheeses,” wrote MIT anthropologist Heather Paxson in her 2012 book, The Life of Cheese: Crafting Food and Value in America. “But while heightened interest in sophisticated European cheeses may have helped open a market for domestic varieties, it also raised the bar.”

The boom of artisan cheese making in this country, especially of aged raw-milk cheeses, provides a window onto the social and regulatory negotiations of what Paxson calls the Pasteurian social order, in which microorganisms are meant to be destroyed. “Although no one is suggesting overthrowing the FDA—a safe food supply is not to be underestimated—a curious mix of political libertarians and foodies is questioning some of the motives and logics underpinning the Pasteurian food regime,” she wrote in a 2008 paper for the journal Cultural Anthropology. In the post-Pasteurian ethos of today’s artisanal cheese cultures, microbes are viewed as ubiquitous, necessary, and flavorful, and that thinking led Paxson to develop the concept of microbiopolitics, the subject of a fascinating chapter in The Life of Cheese.

She credits microbiopolitics for new alliances among cheese makers, farmers, scientists, merchants, and foodies—as well as networks such as the Cheese of Choice Coalition, formed by the American Cheese Society and Oldways in 2000, and dedicated to protecting Americans’ right to eat raw-milk cheese. In association with the Guilde Internationale des Fromagers, it’s sponsoring an international Raw-Milk Cheese Appreciation Day this coming Saturday, April 18; you’ll find a list of participants on the dedicated Web page and in-store tastings at many local cheese shops.

“In the landscape of artisan cheese today, you can find great stuff throughout the country,” Roberts pointed out. “And you shouldn’t be shy about asking ‘Can I taste this?’ ”

And while you savor that one cheese, keep in mind that there are thousands more out there.