Sandor Katz is a culinary author, DIY food activist and self-described "fermentation fetishist." He has taught hundreds of food fermentation workshops around the United States and his book Wild Fermentation has been called a classic, "the bible for people embarking on DIY projects like sourdough or sauerkraut", and "especially notorious for getting people excited about fermenting food". In 2009, he was named as one of CHOW Magazine's "CHOW 13" - their top trendsetters and rabble-rousers.

 Katz, who is openly gay, grew up in New York City and now lives in a rural, off-the-grid Radical Faerie community in Tennessee.

He was the subject of the song "Human(e) Meat (The Flensing of Sandor Katz)" by punk rock band Propagandhi, a satirical vegan response to the "Vegetarian Ethics and Humane Meat" chapter of Katz's book The Revolution Will Not Be Microwaved.

Interview carried out by email by Jack Little in May 2013. Published in issue 30.

1. Before we begin, what actually is the process of fermentation?

Biologists define fermentation as the cellular process of producing energy without oxygen, anaerobic metabolism. The cells of our very bodies are capable of this, and indeed, most fermented foods and beverages are produced by processes that fit this definition. However, there are certain foods and beverages universally understood as ferments that require oxygen (vinegar, for example), so I prefer to use a broader lay definition in which fermentation is the transformative action of microorganisms. Yet this is too broad, since we generally do not describe rotting food, or even a compost pile, as fermenting. So really, we reserve this word to describe microbial transformations that are intentional.

2. How did your passion for fermentation come about?

My interest in fermentation evolved over time. As a kid, I loved sour pickles and other foods flavored by lactic acid produced by fermentation. In my twenties, I followed a macrobiotic diet for a couple of years and began to learn about the digestive stimulation of live-culture ferments. But it was only after I moved from New York City to rural Tennessee and started keeping a garden that I started practicing fermentation. It was a combination of the practical benefits of food preservation, the incredible flavors, the healthiness of live bacterial cultures, and the magic alchemy of cultivating microorganisms that appealed to me. I was also living in a community where my service work was in the garden and the kitchen, so once I got interested I had the opportunity to indulge my interest and it developed into a full-on obsession.

3. Do your fans and readers tend to come from similar backgrounds with
overlapping ideas and ideologies?

Not at all. Everybody loves fermented foods and beverages, and food transcends all ideology.

4. Whilst researching for your books, what did you find out about the
process of fermentation across different cultures?

Fermentation is practiced everywhere, with a huge amount of variety and distinctiveness, but also broad patterns of similarity. With human migrations around the world, crops, animals and how to use them have all spread and influenced everywhere else. Fermentation is a fascinating lens through which to view cultural similarities and differences.

5. What are the economic and health benefits of consuming fermented foods?

Human settlement would never have been possible in many parts of the world without fermentation as a means to preserve food from seasons of plenty to feed people through seasons of scarcity. For farmers, ferments are the classic value-added products the facilitate trade and transport. In terms of the contemporary locavore movement, in most temperate regions, fermented foods are important means of eating locally through the winter.

As for health benefits, fermented foods are pre-digested, making certain nutrients much more bio-available and breaking down certain toxic compounds. Some ferments also have enhanced vitamin content, as well as metabolic by-products that can have powerful therapeutic benefits. Bacterially fermented foods that are not heated after fermentation and have their bacterial populations intact can have probiotic benefit, replenishing and diversifying the gut microbiota.

6. Are there any health dangers associated with eating fermented foods?

Enjoy fermented foods and beverages in moderation. They have powerful effects and strong flavors and need to be respected. Eat them often rather than in large quantities. There is research indicating that high consumption of salty foods, including fermented ones, can cause many different problems. Ferments do not have to be salty, or consumed in large quantities. Some research in Asia has suggested a correlation between high consumption of preserved vegetables and esophageal, nasopharyngeal, and some other cancers. Yet eating fresh fruits and vegetables has been found to reduce incidence of the same cancers. Again, moderation and diversity must guide our diets. Finally, frequent consumption of highly acidic foods can erode tooth enamel. Rinse your mouth with water and brush your teeth after you eat!

7. Do fermented foods taste different to processed foods from the supermarket?

In fact, many processed foods in the supermarket are ferments. Many common foods, such as bread, cheese, cured meats, coffee, chocolate, beer, and many others are products of fermentation. But the differences between home and small-batch fermented foods and those industrially fermented can be dramatic.

8. Your books have been translated into Spanish. How were these received?

Wild Fermentation was only recently published in Spanish, which thrills me. But it has only been a few months and I have not received feedback beyond a few emails. Wild Fermentation has also been translated into Korean, and The Art of Fermentation is being translated into Chinese and Portuguese.

9. You are openly gay. Are you involved with gay rights projects in the USA?

I have been involved in civil rights activism for most of my life, speaking out for the rights of all people and especially the most vulnerable and marginalized. It’s been amazing to witness the growing social acceptance of gays and lesbians, but still discrimination and violence, against queers of varied description, is widespread. Alas, my rural life (the past 20 years) has been much less activist-oriented than the earlier urban period. But in the work that I have been doing, I always seek to mentor young queers, and always try to make my queerness visible.

10. How has your research and teaching in fermentation changed your life?

I began writing Wild Fermentation after a period of debilitating illness, in which I came to accept that I could be dying. My work writing and teaching about fermentation has given my life a renewed sense of purpose. It is deeply gratifying to find so much interest in the topic.