Swetha Sivakumar on how to brew your kombucha just right
It’s been a couple of years since kombucha entered our vocabularies and pantries. But brewing a perfect batch involves a biology lesson on bacteria and yeast. Where do its antioxidants come from? When is it probiotic? Find out here
The Chinese word for tea is “cha”. Kombucha is said to have originated in China. It refers to a type of fermented sweet tea. To make kombucha, tea is first brewed in water. Then sugar is added, which provides the necessary food for the microorganisms to come. To this beverage, SCOBY, a Symbiotic Culture of Bacteria and Yeast, is introduced. The bacteria create a tartness similar to that in yogurt, and the yeast creates a fizziness like in a soda drink. This SCOBY is left to grow and ferment in large tanks of kombucha for anywhere from 8 to 45 days. The SCOBY grows over time, getting larger and larger. It is then fished out, leaving little bits and pieces in the drink. The fermented drink is bottled and shipped.
Kombucha is widely regarded as a probiotic drink. But sometimes it is difficult for manufacturers to sustain the live cultures in the final packaged bottle. The SCOBY that remains in the bottle keeps producing alcohol over time, and this is a problem. Alcohol levels must be kept under 0.5%, or a drink has to be sold separately as an alcoholic beverage.
To prevent the production of excess alcohol, some companies wipe out the SCOBY, to create a shelf-stable drink. The drink retains the fermented, tart flavour and fizzy nature, just not the live cultures. These products carry labels such as “sparkling fermented tea” or “with antioxidants” rather than the word “probiotic.” The antioxidants refer to the antioxidants found in the original tea.
The only way to get kombucha that has the probiotic benefits is to get a refrigerated bottle that clearly states that it “Contains live probiotics.” These companies can do this in two ways. One way is to micro-filter the yeast out but retain the bacteria part of the SCOBY, thus allowing it to be labelled “probiotic”. Another method is alcohol extraction, a technique used by the wine industry to produce non-alcoholic wines. This keeps everything intact in the drink except for the alcohol, using methods such as reverse osmosis.