If you have friends who brew kombucha, ask around for kefir grains, have a jar of kimchi bubbling away on the counter, or wax poetic about salty dill pickles fermented in brine, you can probably thank Sandor Katz.The grandson of Jewish immigrants who came to New York from Belarus in 1920, Katz grew up on the Upper West Side, and has written about his fond memories of “yummy garlic-dill sour pickles [from] Guss’ pickle stall on the Lower East Side of Manhattan and Zabar’s on the Upper West Side.”After deciding he needed to make a change in his life, Katz moved to a commune in rural Tennessee in 1993, where he discovered that “in a garden, all the radishes and cabbages are ready at the same time, and just as a practical matter I thought I’d better learn how to make sauerkraut.”Katz became so taken with the practice (his Twitter handle is @sandorkraut), that he soon began to seek out how to make other fermented foods. And since the publication of his book Wild Fermentation in 2003—and the five-month-long book-and-sauerkraut demonstration tour that followed—he’s found himself increasingly in demand as a speaker.“It’s just evident there is a huge interest in this,” Katz tells me over a glass of iced tea at a café in Halifax’s North End. “The last few years it’s been consistently big crowds.”Katz was making his first visit to Nova Scotia at the invitation of Av Singh, chair of the Centre for Small Farms, an organization dedicated to promoting sustainable food practices. Over a week he would offer five workshops, in settings as varied as a farmers’ market, a university, and a small vegan restaurant.Although it’s been over a decade since the publication of Wild Fermentation, 2014 has been Katz’s busiest year yet. He’s spent a month in Australia and New Zealand, toured New England and the South, and also been to Ireland, the U.K., Belgium, and Sweden.“One of the things I like to do is relate fermentation to bigger themes. I’ve developed this theory that agriculture would not be possible without fermentation,” Katz says. “Basically, people never could have developed practices in which they invest their time and resources into crops that are ready at certain moments of the year, if they didn’t have some good insight into how to preserve those crops so that they could get them through the rest of the year—and in practically every case, that involves fermentation.”Of course, one of the downsides of this schedule is that Katz rarely has time to tend to his own fermentation practice anymore. (His cherished kefir grains are being cared for by a neighbor in his absence.)“I feel really torn about it,” Katz says. “What got me interested in fermentation was the 10 years I spent living on this commune, playing in the garden and playing in the kitchen, and I don’t have much time these days to do those things. I love traveling, I love the missionary work that I do spreading information about fermentation, but I’m continually trying to find a balance. That is a struggle in my life for sure. I could be quite happy hardly ever leaving home.”The balance would have to wait, though. A few days after I met Katz, he was heading to northern India to teach in a month-long course at Navdanya–the institute founded by anti-GMO and heritage seed activist Vandana Shiva. Part of what he hopes to do there is expand on the links between fermentation and soil microbiology.And while some people might be looking forward to seeing the sights, Katz has different priorities. “I’m really excited to see the diversity of fermented milks in India. All over the world, people have developed different practices for culturing milk. I think of forms of fermented milk like languages—and many of them are being lost.”Philip Moscovitch is a freelance writer and broadcaster who moved to Halifax from Montreal 15 years ago. Follow him on Twitter @PhilMoscovitchRelated: Distilling the Taste of Morocco\nWant To Make Your Ordinary Sandwich Extraordinary? Add a Turnip. Seriously.