Kombucha, a beverage made from fermented sweet tea, originated in China about 2,000 years ago and has enjoyed a more recent renaissance in the United States. You can often find it in bars as the basis for virgin cocktails as well. It's most commonly served chilled; too much heat can reduce the probiotic benefits.
What Is Kombucha?
Kombucha uses a symbiotic colony of bacteria and yeast called a SCOBY to produce a very slightly alcoholic and mildly acidic beverage often enjoyed for its tart flavor and effervescence. Because most of the alcohol turns into acetic acid, commercially produced kombucha is sold as a non-alcoholic beverage.
How to Make Kombucha
Kombucha can be made from any variety of tea, most often black, green, oolong, or yerba mate. Sugar provides the fuel for fermentation. Honey, with its antimicrobial properties, generally does not work for making kombucha. A bacterial "mother," or culture starter, begins the fermentation. The brew sits for one week to one month, during which time the culture grows and feasts on the sugar. Once it reaches the desired taste, the liquid and the SCOBY get separated to halt fermentation. Flavors such as fruit or herbs can be introduced during the bottling process.
The bacteria and yeast culture form a slime-like clump of cellulose in the beverage, which can be transferred to a new batch of kombucha to continue the fermentation process. Strands of these bacterial cellulose clumps can be seen inside bottles of commercially sold kombucha. Although edible, the texture makes it undesirable for consumption.
The acetic acid production usually keeps the acidity of the beverage around a pH of 3.0. The alcohol and pH of kombucha are usually enough to prevent contamination from undesired bacteria, mold, and fungus. If the batch does become contaminated, the tea, as well as the culture starter, must be discarded.
What Does It Taste Like?
The flavor of kombucha relies heavily on the type of tea, the sweetener used to fuel fermentation, and the unique blend of bacteria and yeast cultures. Additions such as fruit, herbs, and spices also affect the final flavor. The longer kombucha ferments, the more vinegary it becomes. In general, kombucha is slightly tart from the acetic acid content and tends to be slightly effervescent due to the production of carbon dioxide during yeast fermentation. There are many brands of kombucha on the market today, with a wide variety of flavors ranging from fruit-infused to spicy to minty.
Once you obtain a SCOBY, either from a kombucha-making friend, through an online purchase, or by growing your own, it's easy enough to make kombucha at home.
Where to Buy Kombucha
Nearly any health food store and most mainstream grocery stores sell bottled kombucha. Some even carry it on draft. You can find it in gas stations and convenience stores, on many restaurant drink menus, and online.
Commercially bottled kombucha should be stored in the refrigerator, where the cold halts the fermentation process. At warm temperatures, a bottle of kombucha can actually explode. Homemade kombucha spends the first several days at a warm room temperature to encourage fermentation, but then it should be bottled and transferred to the refrigerator for longer storage.