Venturing Into the World of Fermentation

Fermentation is one of the oldest methods of preserving food. (casanisa/Shutterstock)

In the early days of human civilization, before there were canning jars, refrigeration, and freezer bags, fermentation was the most common way to preserve food. To this day, many of our favorite delicacies, including booze and chocolate, depend on the process.

But a lot of home cooks and food savers, myself included, feel intimidated by the prospect. We’re more likely to make vinegar pickles than fermented sour pickles, in part because the rules are clearer with canning. There’s less sniffing involved.

Conceptually, fermentation is the antithesis of most conventional food preservation techniques, as it encourages bacterial growth while most other techniques aim to create a sterile environment in a quest for suspended, lifeless animation. Fermented food doesn’t usually look anything like what it once did, but it’s alive, still, with microorganisms, the enzymes of which preserve food by transforming it, converting sugars into alcohol and acids.

There has never been a case of food poisoning from the fermentation of vegetables, I was told by Sandor Katz, a teacher, author and, first and foremost, fermenter, who is soon coming to my neck of the woods to keynote a gathering of fermenters.

“You could end up with a mushy texture that you hate, or end up with a surface growth that’s ugly and scares you, but there’s no case history of making anyone sick,“ Katz said. ”I’ve definitely thrown stuff away. I’ve removed a top layer. But I’ve discovered that the bottom is fine. The surface phenomenon is almost always caused by oxygen.”

One of his newer pet ferments is a Chinese brine called pao cai (pronounced “pao tsai”). It’s made with spice mixes that vary from region to region in China. Some of the seasonings are familiar, like ginger and garlic, and some are Chinese herbs that are less known, but certainly available at Chinese herb stores or online.

Katz details this brine in his new book, “Fermentation Journeys,” which is based on his worldwide travels and the ferments he discovered along the way. He'll unveil his pao cai as well as other tricks this September in Montana at his first live workshop since the pandemic hit, and he’s excited. “It’s been wonderful to connect with people via Zoom given the circumstances, but food is all about flavors and smells and direct sensory experience, which isn’t possible when teaching remotely online.”

A Fermentation Education

I barely know the basics of fermentation, though I’ve got pretty much every other preservation technique down, from blanching and freezing my green vegetables to the perfect pickled peppers, to any of my tomato products. But I’ve always avoided fermentation like some final frontier I wasn’t worthy or ready to breach.

To help get up to speed before Katz shows up, I drove out to a local commercial food kitchen to meet Erin Belmont, a local fermenter and co-organizer of the Bacteria Bazaar festival. She was making a batch of pepper paste for her House of Ferments label of fermented products, and I was there to follow along and make my own batch to bring home.

I’ve been a fan of fermented pepper paste since long before I knew it was fermented. My friend Pedro used to bring it home from Panama. Then I got some at a West African restaurant in New Mexico. When I tried some of Erin’s, I realized that the unmistakable flavor I’d fallen in love with was fermented. And after a few minutes in Erin’s rented kitchen, it was clear that preparing a reasonable-sized batch of Panama Hot Sauce is less work than making a salad on most days—with the caveat that, unlike a salad or most other dishes, a ferment needs to be stewarded for weeks after it’s been made, like carefully docking a ship in port. But slower.

First, we cleaned and weighed some fresh habanero and mini yellow peppers. It was all I could find at the store in early July that wasn’t green or a sweet bell, both of which were off-limits, she said. Erin herself was using dried peppers from last year, which she’d purchased in bulk from a farmer named Mr. Sunshine.

Erin Belmont divulges the proprietary mix of Mr. Sunshine peppers that go into her hot sauce. (Ari LeVaux)

My peppers came out to 1,217 grams. We put them in a food processor with a few cloves of garlic, and added 24 grams of salt for about a 2 percent brine—standard for a vegetable ferment.

“I’m tempted to add more salt,” Erin mused. This leeway, this wiggle room, this ability to steer, steward, and even season your ferment and ultimately get it where you want it, is part of the attraction. My wife, a solid fermenter herself, admits as much. She recently used 2 percent salt and cabbage to make an absolutely perfect batch of sauerkraut. She also makes jun tea, a type of kombucha made from green tea and honey, and of course she has a sourdough starter, named Savage.

Keeping It Together

I brought home my activated pepper paste and set it on the shelf, with the lid loose so gas could escape as the fermentation began. I’d give it a gentle shake every day, because it seemed to want to separate into liquid below and pepper paste up top. Each time I shook it around, it would foam a bit and then settle.

The author's fermented hot sauce, version 1. (Ari LeVaux)

After about a week, I could taste the fermentation happening. It was promising, but evolving slowly, and I wasn’t happy with how it kept separating, and the daily shaking routine to keep the ferment active didn’t feel right. I added more salt, and things got right in a hurry. Within days, which is just a few moments in Fermentation Time, the separated pulp and liquid recombined into a homogenous mixture. And the flavor became sharply more acidic, which made it more interesting and satisfying and useful.

The reason I was so stressed about my separating paste is that, to paraphrase Katz, oxygen can make things ugly at the surface of the ferment. If I hadn’t been able to get it to mix, my wife says, I’d have had to weight it down somehow or risk a bad outcome. She weights her sauerkraut down with a bag of water, “but what I really want is a boiled river rock,” she says.

My pepper paste hasn’t separated since I added salt, but I can’t say it has yet hit full maturity. And I can’t say it’s ever going to reach full maturity at the rate I’ve been “evaluating” it, especially since adding the salt. Lately, I’ve enjoyed evaluating it mixed with mayonnaise and chopped fresh onions atop tomato slices. I don’t know what tomorrow will brine. I mean bring.

Ari LeVaux writes about food in Missoula, Mont.