The Food and Drug Administration requires that what is labeled vinegar contain four or more grams of acetic acid per 100 milliliters. That acid, produced when certain bacteria metabolize alcohol, is what broadly defines vinegar and its flavor — the sharpness on your tongue, the prickling in your nostrils.
But vinegar enthusiasts, including a growing group of chefs and home cooks across the country, have a far more nuanced understanding. And what Mr. Lee makes is only distantly related to the harsh, distilled vinegars used for household tasks, or diluted for basic brines.
The word comes from the French vin aigre, or sour wine, but great vinegars can be made from the slow, controlled fermentations of many different fruits, vegetables, grains and syrups. They can be cloudy or clear, mouth-puckering or sweet, fruity or gamy, with endless variations.
“A great vinegar has all the characteristics of the initial product — that’s the most important thing,” said Harry Rosenblum, the author of the 2017 book “Vinegar Revival” and a founder of the Brooklyn Kitchen, a cooking school with two locations in New York.
Mr. Rosenblum sees the uptick of interest in quality vinegar as a part of the home-brewing and fermentation movements — an ingredient with history, and roots all over the world, that also welcomes creativity.
Making your own vinegar isn’t foolproof, but part of its appeal is that it requires little in the way of an initial investment, and few tools. (Though serious vinegar-makers may rely on pH meters and other gadgets, a wide-mouthed jar and a piece of cheesecloth are all you really need to get started.)
Vinegar, the result of acetic fermentation, simply requires oxygen, bacteria and alcohol. You can start the process with ready-made alcohol — a bottle of wine, sake or cider — or create your own alcohol by fermenting fresh peaches or coconut water. From there, the microbes get to work, turning the alcohol into vinegar.
Mr. Lee has a space-saving method at his restaurant. He seals fruit with sugar and water in clear plastic bags and stacks these on sheet pans in the walk-in refrigerator. As the fruit rots, the bags puff. But before they burst open, Mr. Lee transfers the contents to finish fermenting in small two- to three-quart jars.
He often draws out the process over several months, until the bacteria start to metabolize the acetic acid itself. Now, the vinegar changes, taking on new layers of flavor. Its sharp edges soften. As it ages, it becomes increasingly mellow.
“For me, good vinegar is something that’s alive,” Mr. Lee said. “It has a good shot of umami; it makes your mouth water.”
In her Dallas apartment, the chef Misti Norris ferments a jumble of vinegars in glass containers and covered oak barrels, in a dark, temperature-controlled nook equipped with a dehumidifier that keeps the vinegars around 65 degrees. Some will mature for a few months, others a year.
“I like to work on things that take a long time,” said Ms. Norris, who runs the pop-up restaurant Petra and the Beast.
When she began making vinegar a few years ago, she was giving bottles away to friends in the restaurant business, but as the taste and demand for great vinegar have increased, so has Ms. Norris’s production. She plans to sell her vinegars later this year, including some made from local mustang grapes, passion fruit, peony flowers and figs, as well as collaborations with local brewers, made from sour beers and fruit-infused saisons.
Jori Jayne Emde, who runs Lady Jayne’s Alchemy in Chatham, N.Y., lets her vinegars ferment slowly, over many months, in an open-air barn. Come winter, she steps away, letting the steel containers freeze where they stand. When the weather warms, she says, the vinegars thaw out and pick up where they left off.
Ms. Emde owns Fish & Game with her husband, the chef Zak Pelaccio, and was drawn to vinegar-making in part as a way to avoid food waste. “All the things that might get put in the trash or composted, I mix with wine and ferment,” she said, “I call it whole utilization.”
She collects food scraps and leftover wine dregs, transforming the miscellany into an array of vinegars, from carrot and tomato to sour cherry and brown bread. The kitchen at Fish & Game uses these bottles, and never fresh citrus, to tinker with the acidity in their dishes, seasoning it on snails roasted with absinthe and garlicky herb butter, or using it to dress winter greens.
Ms. Emde works with six-gallon steel drums full of pith, seeds, stems, tops, peels and cores fermenting in a base of wine. She lets the vinegars sour naturally, without a starter, and develop acetic acid over time. But since her production is outdoors, she occasionally takes the spent yeast from previous batches and splashes it around the barn. She says it ensures that the microbes she values, the ones she wants in the vinegars, are thriving nearby.
Many vinegar-makers will speed up the process slightly with a mother — a jellylike disk of acetobacteria and cellulose that may form naturally on the top of a vinegar as it ferments, or can be bought online.
In his book “On Food and Cooking,” the science writer Harold McGee calls vinegar “alcohol’s fate,” neatly summing up both its process and history, which goes back as far as the making of wine, beer and mead.
The earliest vinegars were likely produced in the Middle East, somewhere along the Euphrates and Tigris Rivers. Before refrigeration, there was simply no way to put the brakes on the fermentation process: Ripe fruit produced alcohol, then charged ahead in warm climates, turning to vinegar.
Michael Harlan Turkell, a writer and photographer who makes honey vinegars in his Brooklyn backyard, traveled the world researching the ingredient for his 2017 cookbook, “Acid Trip.”
“Vinegar probably wasn’t a culinary ingredient until around 1500 B.C.,” he said. Around that time, it was used not only as a preservative but also as a flavoring agent, poured over noodles in China, and forming the base of dipping sauces.
Once vinegar made the leap, it persisted. Like alcohol, vinegar was refined all over the world in different ways, shaping cuisines as both a preservative and a flavoring. Where nipa palms and coconuts grew, vinegar could be made from sap and water. Where rice and sugar cane grew, it could be made from sake and juice.
In Paris, Mr. Harlan Turkell met the French chef Bertrand Auboyneau, who used a generous amount of rich, tannic red wine vinegar to brighten oeufs en meurette, the bistro dish of poached eggs in a red-wine sauce. And at a cooking school in Tokyo, the Japanese instructor Naoyuki Yanagihara taught him to make sumiso, the yolk-rich sauce seasoned with rice vinegar and white miso.
Ms. Norris, the Dallas chef, emulsifies her vinegar made from foraged Texan grapes into melted butter and uses it like a sauce to dress pasta. The more rounded, fruity vinegars end up in her desserts, like a mustang grape and white chocolate tart, made with sunflower and passion fruit seeds.
“I think that balance of salt, acid and fat is what makes people want to eat,” Ms. Norris said. “Vinegars can add such subtle nuances, and so much character.”
Mashama Bailey, the chef and owner of the Grey, in Savannah, Ga., compared her use of sherry vinegar and white balsamic to a little squeeze of lemon, brightening everything up just before it’s served. The better the vinegar, she said, the fewer other ingredients, and less cooking the dish needs to shine.
“When you have a really beautiful aged balsamic, you drizzle a little on a piece of cheese,” said Ms. Bailey, “and it becomes the star.”
When vinegar makers get talking, they sound a little like wine lovers. They refer to the expression of the fruit, the structure of the flavors, the complexity of aromas in the nose.
“We’re going from rotten fruit to this beautiful, flavorful, elegant acidic thing that you can drink,” Mr. Lee said. After a decade of making vinegar from scratch, he added, the process remains somewhat mysterious to him. “Things are so scientific, and so standardized in the kitchen. We’ve figured it all out. But not vinegar!”
About 20 percent of the time, the vinegar doesn’t work out, he said. A spore mold finds its way into the jar, ruining the entire batch. Or the liquid becomes too rich in ammonia or somewhat rancid-tasting, or everything turns the bad kind of moldy.
His cooks find vinegar’s lack of certainty irritating, but for Mr. Lee, it only underscores his affection.
“Every time I make a vinegar and it works out, it’s like a minor miracle,” he said. “I’m over the moon.”