Move over, soy milk and wheat-grass juice. The elixir of the moment is a fermented tea promoted for health benefits ranging from improved digestion to cancer prevention.
Called kombucha, it is a drink with a dual identity. There's the commercial version that comes in pretty pastels and fetches upward of $3 a bottle at natural foods stores. And there's the brown, pennies-per-serving home-brew, made with a scary-looking blob of bacteria.
Whether store-bought or homemade, the drink has grown popular with fans of "probiotic" foods, which contain live bacteria cultures. Americans shelled out more than $295 million for commercial kombucha and other so-called functional juice drinks last year, up from just under $270 million in 2008, according to SPINS, a market research and consulting firm for the natural-products industry.
Not bad for a drink that even fans compare to vinegar. Consider how Seth Goldman, president of Bethesda-based Honest Tea, describes the beverage his company added to its line in November.
"What's so striking is, on the first taste, it's not immediately appealing to people," Goldman said. "It's got an acidic taste to it. … It's not the kind of drink that would be around if it sold only on the merits of taste."
So what is it that makes a vinegary drink worthy of a frappuccino-quality splurge? Or, for those going the home-brew route, worthy of devoting counter space to something that looks supremely unappetizing?
Better gastrointestinal health. A boosted immune system. More energy. Improved skin and hair. Not to mention a cancer-free existence. At least that's what some devotees think they can get out of the drink, whose roots are traced to an ancient Chinese tea and to Russian kvass, the fermented drink made from bread.
But some medical experts question the health claims and consider the homemade version dangerous because of the potential for unhealthful bacteria getting into the mix. The commercial variety is generally considered safe because it is made under sterile conditions. But just last week, Whole Foods pulled all brands of kombucha from its shelves after determining that it contained more than the usual trace amount of alcohol.
Honest Tea tests each batch to make sure it does not exceed 0.5 percent alcohol. The company is investigating what might have caused the alcohol level to rise after bottling. Honest Tea's kombucha remains available at other natural foods stores around the country, including Mom's Organic and Roots markets in Maryland.
There have also been concerns that the drink can lead to a potentially fatal buildup of lactic acid in the blood known as lactic acidosis. In 1995, when the drink first caught on with American AIDS patients and others looking for an immune-system boost, the Centers for Disease Control warned that homemade kombucha tea might have played a role in the death of one woman and the severe illness of another in a rural town in northwestern Iowa. It also warned that there was a risk of lead poisoning if kombucha is made in ceramic pots.
None of which has deterred kombucha devotees, some of whom delight in the do-it-yourself aspect of the home-brew.
The process starts with yeast-bacteria "mother," a gelatinous disk often compared to a jellyfish and sometimes referred to as a mushroom. Think sourdough starter, but for a drink instead of bread. Like the bread starter, bits of the kombucha mother are often shared among friends.
The mother goes into a jar. Added to that is tea that been brewed, sweetened and then cooled, so as not to kill the live bacteria in the mother. Then the whole thing sits at room temperature to ferment for five to 10 days, becoming slightly bubbly and progressively tangy. When it becomes too sour, the liquid gets dumped out and a new batch of tea is added to the mother, which is kept indefinitely.
Aliza Sollins, 27, of Hampden, acquired her kombucha mother about two years ago from a friend of a friend. She has been making the tea ever since.
"My boyfriend is a chemist and saw me feeding the kombucha, and he said, 'Oh my God, I would totally sterilize everything every time,' " Sollins said. "I do try and make sure everything is sterilized and keep it clean. You really have to trust yourself. I do home canning, too. You have to know basic food safety."
Dubbed "the fermented foods queen" by a friend, Sollins keeps sourdough starter in her fridge, has brewed her own beer and made kimchi. She even attended a fermented-foods potluck dinner thrown by a local food-makers group, where she sampled a Japanese pickles made by fermenting vegetables in a mash of seaweed, salt and roasted rice bran.
"I happen to like tangy things," said Sollins, who works in the admissions office at Maryland Institute College of Art and writes a blog called BaltimoreDIY (at baltimorediy.blogspot.com).
She also thinks there are health benefits to fermented foods, which she said "give me more energy." She doesn't buy into some of the "really intense health claims" sometimes associated with kombucha, but she finds the sour fizzy drink settles her stomach when she's had too much to eat.
"For me, personally, it makes me feel a little bit better," she said.
There might be something to that, according to Dr. Gerard Mullin, associate professor of medicine at the Johns Hopkins School of Medicine and director of Hopkins' integrative gastrointestinal nutrition services.
"Fermented foods can be good for your intestines," he said. "They can help the friendly bacteria thrive. These are all probiotic foods. Because they're byproducts of fermentation, they can help the friendly flora. … These little bugs we've been ignoring all these years — what we eat depends on whether the good guys or bad guys thrive."
That said, he would not recommend making kombucha at home because of the risk that bad bacteria could get into the mix.
Diane Hoffman, director of the Law and Health Care Program at the University of Maryland's law school, questioned whether there are any health benefits to probiotics in general. She is leading a three-year study, conducted by the university's law and medical schools, attorneys, scientists and industry experts, into the health claims made for probiotic products.
"The literature showing benefits or effectiveness is generally quite weak for probiotics broadly," she said. "It seems there are many more claims being made than there is evidence of effectiveness."
Honest Tea's website makes only vague health claims: "Once referred to as 'elixir of life,' the health benefits of kombucha have been enjoyed by many cultures for centuries."
"Of course, you're not officially allowed to make health claims with just about anything, but we know people appreciate the probiotic content of the drink," Goldman, the Honest Tea president, said in an interview. "Active probiotic cultures are believed to play an important role in digestion and a whole range of functions."
Mattan Schuchman, 26, of Baltimore, has been making kombucha for about two years until recently, when he discovered mold growing on the yeast-bacteria "mother."
He was never in it for the taste.
"I tried to convince myself I liked it in the beginning," he said. "But to be really honest with you, it's not super-tasty."
Nor was Schuchman, a second-year medical student at the University of Maryland, doing it for his health.
"I looked into some research about it, and my conclusion with kombucha is, most of the health benefits are completely anecdotal," he said.
Schuchman simply enjoyed the engagingly gross science-experiment aspect of having a living thing floating in a vat of tea that he could drink.
"It was kind of like a pet," he said. "We named our mother. We called her Mother Teresa. She's kind of like a little part of the family."
When his kombucha mom turned up moldy, Schuchman couldn't bear to throw it in the garbage. He got a neighbor to put it in her compost pile, where Mother Teresa could live on.
"It just felt so wrong to throw it away in the trash," he said. "She's alive."