From chocolate to cheese, salami, wine, pickles and bread, many of the world’s greatest delicacies are the products of fermentation. However, it wasn’t so long ago in our antibacterial-obsessed culture that cheesemakers and chocolatiers downplayed the role of bacteria in their processes.
“We grew up with germ theory, antibacterial soap and the mantra, ‘Don’t leave it out; it will kill you!’ — those messages are deep in our psyche,” says Kirsten Shockey, co-author with (her husband Christopher Shockey) of Fiery Ferments (Storey Publishing, 2017) and Fermented Vegetables (Storey Publishing, 2014). That view is changing though, as our culture increasingly embraces live cultures for their health benefits and the exciting flavors they impart.
Fermentation is defined as the chemical breakdown of a substance by bacteria, yeasts or other microorganisms, usually involving effervescence and the emission of heat. For some 9,000 years, humans have manipulated this process to encourage certain strains of bacteria or fungi to grow in vegetables, grains and dairy products to preserve them and add flavor.
Types of Fermentation
The most common form of fermentation is lactic acid fermentation, which is used for making kimchi, yogurt and certain kinds of pickles. Other common types include acetic fermentation (vinegar production) and alcoholic fermentation (occurring in distillation).
“All of the food we eat is populated by various communities of microorganisms, so there isn’t just one in play,” says Sandor Katz, author of the James Beard award-winning book The Art of Fermentation, and a self-avowed fermentation revivalist. “Fermentation is simply a manipulation of scientific conditions to encourage the growth of some organisms and discourage the growth of others.”
Lactic fermentation occurs in both sauerkraut and charcuterie, for example, when bacterial enzymes transform protein into amino acids. Moisture is essential to inhibiting bad bacteria in the former but detrimental to the latter. In that case, trapped moisture can lead to spoilage.
Vegetable fermentation is a great gateway to other kinds of fermentation because it’s simple to make and, frankly, hard to screw up. “You don’t even need a starter — just vegetables, salt, a vessel and time,” Shockey says.
Sliced, shredded or mashed produce is submerged completely in salted liquid — by either suspending it in a salt brine or massaging it with salt to release its juices — to create an anaerobic environment that locks out oxygen’s entry.