Authentic Kombucha, in its purest, raw form, contains live bacterial cultures that need to be refrigerated to maintain potency and.... “Shelf stable” kombucha means it has been through a pasteurization process, thus killing these live cultures and enzymes and stripping it of it's most beneficial properties. How would you feel about shelf stable yogurt? Would you buy it? Not likely. The same applies to your kombucha.
Shelf stable kombucha generally contains added preservatives and a higher sugar content and is manufactured this way to cut costs and extend shelf life. This manipulation puts the beverage into a whole different category and should not be considered a Kombucha. Real kombucha, its its raw, unpasteurized state should be stored between 4 and 6 degrees to keep the natural cultures alive and kicking and slow the continuous fermentation to almost nothing. If it is left unrefrigerated, it won't go off, but it will continue to ferment and after a short period of time, will build up too much pressure inside the bottle/can and explode (resulting in a very messy kombucha shower!)
The kombucha market is booming but there is confusion building for consumers. As the category continues to grow, more and more "kombucha' type beverages are appearing on the shelf. It is now more important than ever, to know the good from the bad.
Spot the difference.
The tea
It is essential to use a caffeinated tea, high in tannins in order to ensure the scoby (mother/starter culture) thrives and ferments properly. The best teas are black or green as they are high in tannins, caffeine and antioxidants. When buying kombucha, if the labels reads “tea flavours or extracts” or contains no tea whatsoever (yes, there are some out there), then it is not authentic kombucha.
Ingredients list
If "kombucha" is listed as an ingredient, then it is a good indicator that the beverage is made of more water and sweeteners/flavourings than actual brewed kombucha. True kombucha should list the live cultures in the first 3 ingredients and they will generally be gluconacetobacter or brettanomyces bruxellensis.
Is it in the Fridge or on shelf?
Is the kombucha you are about to buy stored in the fridge or on the shelf? We now know the importance of refrigerated kombucha, so if your chosen brand is sitting warm and snug on the shelf, rubbing shoulders with long life milk and room temperature soda, then don't waste your money.
Expiry date
Raw, unpasteurized kombucha should display an expiry date no longer than 6-8 months. While kombucha doesn't technically expire if it is kept refrigerated, all market brands that are producing authentic kombucha will set an expiry date of 6-8 months to ensure maximum potency and flavour for the consumer.
Sugar
Two things to address here.
1 - If sugar is not a listed ingredient then that kombucha has likely not been through a proper fermentation process. Sugar is needed to feed the yeast in the initial fermentation. During this process, the sugar (and caffeine) is metabolised and depending at what stage the fermentation is stopped, the residual sugar content should be very low. Typically, kombucha should be fermented no less than 30 days to reduce the majority of the sugar.
2 - Traditionally, kombucha is a healthy, immune boosting, disease fighting, gut building beverage. It is not a pop. If your kombucha contains over 10g sugar per serving, it is likely than additional sugar has been added for flavouring, post fermentation. This does necessarily question its authenticity, but a high sugar content does go against kombucha's healthy profile. If you are looking for a refreshing, better for your alternative to energy drinks or pop, then a kombucha that contains the same or even more levels of sugar is not your best option.
The taste
Kombucha is a fermented beverage. Therefore, naturally it should have a slight tangy flavour. This shouldn't be overpowering or off putting, and some brands taste more vinegar-like than others. It’s all down to preference and kombucha category now offers quite a variety. However, if there is not even the slightest hint of tanginess, then it might suggest that either no tea has been used or it is made from a kombucha concentrate with too much added water.