Only a sugar-laden kombucha needs a fridge

kombucha is an ancient fermented drink. Before electricity, it was already made and preserved without a fridge. Industrial refrigeration arrived 150 years ago; kombucha has been around for over 2,000. The reason many modern kombuchas need refrigeration is not for safety: it's due to the residual sugar left when bottled.

The origins of kombucha

The origins of kombucha are somewhat uncertain. According to the first written references, this fermented drink, which everyone is talking about today, was born in ancient China, the cradle of tea, around 221 BC. It seems that during the Han dynasty, Emperor Qin Shi Tsin drank it for the first time and was able to verify its benefits.

However, given that black tea was born much earlier —documented between 1600-1046 BC—, it is possible that kombucha emerged spontaneously about eight centuries before being referenced in writing. It is difficult to know the exact date of kombucha's actual birth. The K-day, when one can say "it (kombucha) was created", is a true unknown.

Even more so when we know that Emperor Shi Huanghti, successor to Qin Shi Tsin and popular for initiating the Great Wall project, was also famous for suppressing literacy and even burning thousands of books documenting the history of this era.

When there were no fridges: time and patience

If finding written references about kombucha is truly complicated, it is even more so to find images about the preparation of what would be called the "elixir of immortality". But if there is one thing we are clear about, and not just for lack of graphic evidence, it is that the first kombucha makers did not have fridges to preserve the kombucha they made. There was no electricity, this is evident. The only ice they would have known was that which formed naturally during the cold of winter.

Most probably, they made kombucha and stored it in a cool place to consume at room temperature. In fact, nothing more was needed to make it: time and patience. Two ingredients that our Mūn kombucha also contains.

Why many kombuchas do need a fridge today

The explanation is chemical, not historical. A poorly fermented or falsely pasteurised kombucha carries two problems that cold disguises:

• High residual sugar. The more sugar left in the bottle, the more fuel the yeasts have to continue fermenting. At room temperature, the second fermentation remains active, pressure rises, alcohol increases, and the kombucha becomes unbalanced. Cold slows down this process, but doesn't solve it: it masks a short fermentation problem.
• Short fermentation. Many industrial brands ferment for 7-10 days instead of 30. More simple sugars and fewer organic acids remain. Result: a biologically unstable kombucha that is only predictable if kept cold.

Commercial cold storage is a logistical solution, not a production one. If the kombucha is well fermented from the outset, a continuous cold chain is not necessary.

How Mūn does it

The fermented teas we have been making since 2015 at Mūn Ferments meet the requirements not to need refrigeration before opening. They only contain between 0.09 and 1.80 grams of sugar per 100 millilitres, values that are absolutely exemplary and the lowest of all unpasteurised kombuchas on the market.

This is possible thanks to a fermentation process of up to 30 days, where acetic bacteria have enough time to oxidise practically all the ethanol produced by the yeasts, leaving organic acids in its place. The longer the fermentation, the less residual sugar is left when bottled, and the less sense it makes to keep it cold.

Once the bottle is opened

However, and to clarify all doubts: we recommend that once you open it —if you don't finish it— you store it in the fridge and consume it within 7 days. The moment you open it, oxygen re-enters the bottle. With that oxygen, the acetic bacteria reactivate and the fermentation process restarts. The drink, despite not losing its properties, could become more acidic and vinegary.

If it turns vinegary: use it

Don't worry if this happens by accident: you can always use the resulting kombucha to make wonderful recipes. Adding it, for example, to a homemade gazpacho or a salad dressing. You'll see, it's quite a discovery. A vinegary kombucha is not a spoiled kombucha: it's practically kombucha vinegar, and that's gold in a kitchen.

The three vinegar tasters

The image illustrating this article is called The Three Vinegar Tasters. They are Confucius, Buddha, and Laozi, author of the oldest book on Taoism. Vinegar is also a fermented product and could be considered a "first cousin" of our esteemed kombucha. The metaphor alludes to how each tradition interprets the same flavour: for one it is sour, for another bitter, for the third sweet. Fermentation, like many things, depends on the framework through which you observe it.

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