You Need a `Mother’
Vinegar and Fermentation
by Elizabeth Gawthrop Riely
Alex Lewin has been foraging for winter vegetables at the Union Square FarmersMarket near the end of the season. He stands under the Urban Homesteaders’ League tent with a handful of parsnips, a couple of large beets, a rutabaga—or is it a turnip, he asks rhetorically. He assures his audience that it doesn’t matter, as both are Brassicas and close cousins.
These vegetables are prime candidates for pickling, he explains, as people have known them to be for thousands of years. He deftly slices the peeled vegetables with his big chef ’s knife and puts them in a bowl. With his hands he mixes salt into the vegetables, two tablespoons per pound. Then he crams them into a wide glass jar, colors contrasting, and smushes them down with the bottom of a smaller jar, leaving space at the top. As he tells us how fermentation works, liquid begins to form at the bottom of the jar. He presses the slices down a few more times and when he has finished his demonstration, we can see the pickle juice rising. A few more days of smushing and these Brassicas will be fermented.
“There’s not a lot of activity in vinegar-making,” Lewin says with dry humor on another occasion. “It’s mostly bacterial.” For thousands of years, long before industrial techniques such as refrigeration, canning and electricity, people have been pickling vegetables this way. As he explains in simple terms, fermentation takes advantage of “good” bacteria to work on sugar in the vegetables to turn them into lactic acid. As the acidity increases, the “bad” microbes find the environment unfriendly. Usually within a temperature range of 50° to 80° F.—colder being too slow and hotter allowing other microbes to compete—the stable ecosystem that fermentation establishes helps break down the vegetables to make their healthful vitamins and enzymes available for human digestion.
Lewin, who teaches at the Cambridge School for Culinary Arts and coaches at the Institute for Integrative Nutrition, is also a mathematician and software engineer. In contrast to his work in high tech, his blog feedmelikeyoumeanit.com considers fermentation almost philosophically. This natural process, drawing on wild yeasts in the atmosphere, has helped people preserve their precious food supplies since prehistory. Vinegar, bread, wine, beer and other alcoholic beverages, corned beef and dry sausages—each of these employs fermentation. Cheese, yogurt, all the soured milks and creams do too, taking bacteria from the air to transform them, as if by magic.
Kimchi, kaposzta, sauerkraut and choucroûte are different types of fermented cabbage dishes, similar to his root vegetable pickles. All are essential to the diet of their northern cultures where Brassicas grow easily, supplying vitamin C and other nutrients not otherwise available in the colder seasons of the year. Lewin, who has an enquiring mind, ponders how the Vikings used fermentation, giving them adequate nourishment on their long voyages. Also the Basques, he adds, who sailed all the way across the North Atlantic to catch and salt cod to bring back to Europe. Where did pickled vegetables fit into their diet?
Carlson Orchards, in Harvard, Massachusetts, is a major producer of fresh apple cider in the Boston region. They also make cider vinegar, the traditional vinegar of New England because the early colonists planted so many apple orchards. Every farmstead had its apple trees. But Carlson’s keeps its vinegar-making operation way out in Shelburne Falls, so that the microbes don’t reach the sweet cider crop and sour it. They can’t have the two processes nearby each other.
Tim Smith makes all of Carlson’s cider, 1,000 gallons a season, at his farm in Shelburne Falls, where his family has lived since 1828 and he is the seventh generation. The fresh-pressed cider is put into 275-gallon tanks, where it undergoes open aerobic fermentation, usually without adding “mother.” The fresh cider becomes hard in two weeks, and in two to three months more turns to vinegar. “There’s plenty of bacteria floating in the air,” Smith says. “Just think of a bottle of wine you left open and how easily it turns to vinegar.” This process works only between 65° and 85°. “Any colder and it won’t work,” he says. The season ends.
The “mother” that Smith was referring to is a mass of mucilaginous, stringy bacteria that lies on the surface of the liquid to make it ferment. Blob is the best word to describe it, unless you want to use the term Mycoderma aceti, which is one type of vinegar-making bacteria. You may have found it in your own jug of fresh cider that you’ve kept a bit longer than you meant and quickly thrown it out.
Alden Cadwell shows me some “mother” floating in a glass jug of crab apple vinegar that he is making in his home in Roslindale. He bought it at Home Brew Emporium in Cambridge, along with the big jug whose top is covered with gauze to give allow air but no “miscreants” to get in, he explains. He has used three different types of crab apple for the cider: one sweet, one sour, one tangy. “I like the depth of flavor” from using them together, he says. It needs three more weeks to “mellow out, when the sharpness will subside.” Then he’ll bottle it without the mother and let it age three more months.
Cadwell, who works as a chef with Season toTaste Catering and Sustainable Food Systems, takes me to what he jokingly calls his “vinegar station” in the basement and shows me several underway. One is a red wine vinegar that is “ever-evolving.” He points out that it needs a replenishment of red wine to give the mother something to work on. In the past, he has made white wine vinegar using the same mother and intends to make malt beer vinegar soon.
Back upstairs, in his refrigerator and cupboards he reveals several experiments he has going. A hot pepper sauce combines white and cider vinegars with red hot peppers: dynamite. He shows me a bottle of Bragg Organic Apple Cider Vinegar with the “mother,” which he found atWhole Foods and used for his crab apple vinegar.Then he offers me a taste of real aceto balsamico from Modena, Italy—the precious original, not the industrial version with caramel flavoring added that’s so popular among Americans today.
In the fridge a jar of smoked pickled okra sits next to one of preserved lemons. “The taste is amazing,” he says of the lemons, which are preserved in salt and their own juice, a method associated with Moroccan cooking. “The rind has a deep, rich flavor, not shrill like fresh lemon,” he tells me. In the fermentation process the pith loses its bitterness. He uses it with pulled pork, chopped in salad dressing, in meat rubs for pork loin, among other ways.
This past fall Cadwell had planned to make quince vinegar, “but I didn’t get enough juice this year,” he explains. “That’s the fun. I wonder if you could make it with tomato juice?” he asks. “I’m not afraid to just try!” He shows me his big backyard garden with two new apple trees he and his wife just planted and a mulberry tree that reaches over the fence. Mulberry vinegar is high on his list for next year.
For these recipes, it’s important to use salt (either coarse or fine) without any additives or anti-caking agents. Vinegar should have at least 5% acidity. These recipes can be produced without the hot water bath sterilization if you keep them refrigerated.
Elizabeth Gawthrop Riely’s articles have appeared in many newspapers and magazines. Her cookbook, A Feast of Fruits, was published by Macmillan in 1993. Her dictionary, The Chef’s Companion (John Wiley & Sons, 3rd edition), remains in print after 27 years. She was editor of The Culinary Times, published by the Schlesinger Library at Radcliffe from 2000 to 2009. Beth can be reached at email@example.com.