Sandor Katz is the self-proclaimed fermentation fetishist and we’d agree he has the knowledge and obsession to claim the title! We’re very excited to be able to bring him to Chicago to the Good Food Festival where he’ll offer an in-depth three hour fermentation workshop and also help us judge our Kimchi Challenge. To give you a sneak peak into his fermentation knowledge, Sandor has graciously allowed us to give you a taste of his new book, The Art of Fermentation. Here, from Chapter 2, is a brief introduction to the benefits of fermented foods:
The Preservation Benefits of Fermentation, and Their Limits
“Try to imagine life without refrigeration, while still maintaining a supply of food to eat. Like most of the people I expect will be reading this book, I have lived all my life in the historical bubble of refrigeration. By its very nature, the refrigerator is a fermentation-slowing device. It enables food to maintain its freshness longer by limiting and slowing—via temperature regulation—not only the metabolic processes of microbes but also the enzymes present in the food that are poised to digest it. I call refrigeration a historical bubble because it has been available for only a few generations, predominantly in more affluent regions of the world where electrical power is readily available, and yet has powerfully distorted our perspectives on food perishability, instilling in us a fear of its absence; and given its high energy requirements, it seems uncertain whether refrigeration will always be so widely available and affordable. It behooves us to safeguard the living legacy of traditional food preservation techniques, including fermentation.
Fermentation can extend the life of food in several ways. First, the organisms that are being cultivated dominate in the food, thus crowding out and preventing the growth of many other bacteria. One of the mechanisms by which they protect themselves is the production of bacteriocins, proteins that are antibacterial against other closely related bacteria. Also, the fermentation organisms’ metabolic by-products—primarily alcohol, lactic acid, and acetic acid, but also carbon dioxide and many others—have inhibiting effects on many microbial and enzymatic processes, thereby helping to maintain a selective environment that limits what can grow and supports food preservation.
However, not all ferments exist to primarily preserve food. For instance, wheat preserves better as dried grain than in the fermented form of bread. And even under refrigeration, tempeh is stable only a few days (longer tempeh storage requires freezing). Alcohol is an effective preservative, used to preserve grape juice (wine), and frequently used to preserve and deliver plant medicine (tinctures). But alcohol (unless concentrated by means other than fermentation) exposed to air ferments to acetic acid, transforming it into vinegar.
Acidification—by lactic acid even more frequently than acetic acid—is the primary means of food preservation by fermentation. “The advantages of acid food fermentations,” according to food scientist and fermentation scholar Keith Steinkraus, are:
(1) they render foods resistant to microbial spoilage and the development of food toxins, (2) they make the foods less likely to transfer pathogenic microorganisms, (3) they generally preserve the foods between the time of harvest and consumption, and (4) they modify the flavor of the original ingredients and often improve the nutritional value.
Preservation through acidification is the story of vinegar, pickles, sauerkraut, kimchi, yogurt, many cheeses, salami, and all sorts of other ferments eaten in different regions of the world. In each case, fermentation greatly extends the edible life of the raw food from which it is made.
To grasp the importance of fermentation in this regard, we must recognize that until quite recently, techniques for preservation were very limited. There were no refrigerators or freezers. In some locations, people worked with ice, but in most places this was not possible. Canning was not developed until the 19th century. Food could simply be kept in a dry and cool spot; or it could be actively dried (microbial activity is suspended without adequate water) using the sun, and/or gentle heat or smoke, and/or salt. Or food could be fermented. Working with mysterious, bubbling life forces, people could acidify foods and thereby create many exquisite—and lasting—delicacies.”
Sandor Ellix Katz is a self-taught fermentation experimentalist. He wrote Wild Fermentation: The Flavor, Nutrition, and Craft of Live-Culture Foods—which Newsweek called “the fermenting bible”—in order to share the fermentation wisdom he had learned, and demystify home fermentation. Since the book’s publication in 2003, Katz has taught hundreds of fermentation workshops across North America and beyond, taking on a role he describes as a “fermentation revivalist.” Now, in The Art of Fermentation, with a decade more experience behind him, the unique opportunity to hear countless stories about fermentation practices, and answering thousands of troubleshooting questions, he’s sharing a more in-depth exploration of the topic.
As you can see, fermented foods are everywhere in your life but perhaps you’re not making them yourself. Don’t miss your chance to spend the day with Sandor to learn how you too can happily ferment in your own home! Revive this traditional foodway for good health and great taste!