Flowing Cultures, Intertwined Lives: If Our Language Were Kombucha

II. Re-Fermentation of Chinese Tea

I was tinkering with my pickle jars at the time, and though the oxygen environment differed, I understood it instinctively in the moment. I could not help but marvel again and again: those ethereal, fleeting aromas that rise and evaporate with the steam from a hot drink – through microbial metabolism and transformation – are amplified and preserved, generating yet more fragrance and layers of flavour.

Shuyu first tasted kombucha at a vegan restaurant in the US. At the time she found it simply sweet and tangy, pleasant on the body, beneficial to gut health, and available in a variety of flavours. When she learned that kombucha’s original fermentation base was tea leaves, as a devoted lover of Chinese tea, her instinct was immediate: Chinese tea’s flavours are already so rich – why add further flavours with fruit and spices?

“Tea” in the sense of modern tea science is classified by degree of oxidation into six major categories: green, yellow, white, oolong, black, and dark. A tea’s flavour is the organic fusion of cultivar, tree age, altitude, terroir, garden management, processing technique, and brewing skill – so many elements and variables, paths crisscrossing in intricate profusion, that tea alone already holds an infinite world. Kombucha reintroduces fermentation into the drinking of tea, enabling a further extension and expansion of its flavours.

So, guided by their own palate and rooted in a love of China, Shuyu and Kiwon’s kombucha experiments use only high-quality tea leaves, sampling across categories and varieties, with no intention of introducing other flavouring agents. They are devoted to exploring tea’s essential flavour, with a fervour and severity that border on the fundamentalist.

Today, kombucha has been absorbed into the food industry – once again, North America leads the way, with food giants entering one after another. It is no longer merely a freshly made house drink in artisan restaurants; in all manner of packaging, its image is increasingly appearing on supermarket shelves and in chiller cabinets.

Industrialised, standardised production has made the synthesis and processing of “flavour” ever simpler and faster. The range of products appears abundant, yet in truth is impoverished. Some “kombucha” has been pasteurised to extend shelf life and stabilise flavour, forcibly halting the fermentation. The fizz of fermentation is then simulated by injecting carbon dioxide. And deactivated “kombucha” cannot be self-brewed at home by perpetuating a starter culture – just as genetically modified seed cannot be saved for the next sowing; it must simply be bought again. For Shuyu and Kiwon, if they do not make it themselves, they will never again taste the flavours they love. This is a choice and an act of reclaiming “fermentation sovereignty”.

Shuyu said, with a hint of excitement, that kombucha was their new “project”. She described how Kiwon tirelessly records the quantities, timing and temperature of every batch, and how a single failed fermentation leaves him deeply disheartened. Her easy spontaneity meets Kiwon’s drive to get to the root of things: Shuyu embraces intuition and mystery, staying open and candid towards the unknown; Kiwon trusts records and analysis, endlessly probing and seeking answers. The re-fermentation of tea is also the re-fermentation of a relationship – truly a new project.

A week later, I called again, carrying a jar of mother brine from my Sichuan pickles. Shuyu already had a pickle jar ready, along with washed and air-dried ingredients. I taught her to make Sichuan pickles, and she passed on to me, by word of mouth, the proportions and precautions for brewing kombucha. It was an exchange, an interaction centred on microorganisms. I got my wish: I adopted a jar of kombucha SCOBY and set out on a new fermentation journey.

The ratio for tea-sugar water they recommended was “1:10:100”. I had already encountered so many “pinches”, “to taste”, and “a spoonful” across written and oral recipes alike that “1:10:100” felt like a genuinely unambiguous parameter. With so many variables in play – the tea base, water quality, sugar source, temperature, time, humidity, air pressure, the vessel – it served as a benchmark, leaving room for variation and adjustment. It was no dogmatic law, yet it became a golden ratio I came to trust with something close to blind faith, like a restaurant a dear friend raves about that, over the years, becomes your own undisputed everyday haunt.

I was eager to start brewing kombucha, but fermentation demands waiting – humans are merely assistants to time and microorganisms. The adopted starter culture, once introduced to the small environment of the home, encountered its “indigenous” microorganisms and gradually formed a new ecology. Between us and the microbes, sharing the same time and place, we adapted to each other, domesticating one another in return.

In summer the culture is vigorous and so, too, are we; harvesting grows more frequent, and the refreshingly cool sweet-and-sour liquid, well chilled, best soothes the suffering of the long, hot summer. Come winter, fermentation slows and we grow listless; I carried the jar into the bedroom and set it on the bookshelf near the radiator, drawing the window plants back to the edge of my desk. Outside, traffic churned endlessly day and night; inside, a delicate, fresh aroma of fermentation filled the room, lending the withered, dry northern winter a faint, moist ambience of tea groves. In this ten-square-metre bedroom, humans, plants, and microorganisms huddled in close intimacy, feeding one another, sharing warmth and oxygen. For kombucha cultured at home, our dwelling can be called its place of origin; our way of living is also the source of its terroir. The flavour of tea, the habits of a person, the climate of a space – all are transformed by microorganisms, fused into a richer texture of life. Every jar of kombucha each of us brews is unique: it can propagate but never be replicated, can renew but never be pasted.

IV. Propagation and Sharing

Before long, my fermentation jars had multiplied from one to four. Kombucha is plural; its fermentation process is never the work of a single organism. The so-called SCOBY is known to be a symbiotic microbial community composed of acetic acid bacteria, yeast, lactic acid bacteria, and more. Each species plays its part, passing the baton to the next, cooperating and reciprocating, warding off intruding microbes, and forming a cohesive, balanced, resilient microbial ecology. And the pellicle that coalesces and proliferates on the surface of the ferment is the tangible embodiment of this microbial commonwealth.

Kombucha is open. Because it is an aerobic fermentation, one can see it, smell it, witness it. It is less that the container holds the microbes than that the microbes enfold the container. I am reminded of what Neale Donald Walsch wrote in Conversations with God: “The soul is the container of the body.” The aroma overflows; joy overflows; and then the starter cultures overflow.

Just as I had received my own starter, I began to share. Production after production, sharing after sharing.

More and more friends around us were joining this kombucha “symbiotic microbial community.” We began visiting one another’s homes, each bringing homemade kombucha. At first, we teased Shuyu by calling her the “Mother Culture” and Kiwon the “Fermentation Father.” After all, every one of our kombucha had originally sprung from their starter cultures, with a “family tree” to trace the lineage back to them. Meanwhile, we too were spreading our own cultures – mycelium branching, sprawling, intertwining. Gradually, without quite planning it, we had grown into an irregular tasting board game – kombucha blind tastings.

At each blind tasting, we numbered every bottle of kombucha brought along, concealing the maker’s information; poured from a fairness pitcher and divided it cup by cup; recorded our impressions and scores on paper, then tallied to select the top ten. And the host who provided the venue would present the “champion” with a small mystery-box gift.

Every gathering was a feast of drinking. We experienced first-hand, in our own bodies, the multiplicity and richness kombucha can express. Different fermentation bases, different lengths of time, different spaces, different makers – every element and variable assembled here, performing freely. We bore witness to the surprises within our expectations: once, three friends all used the same smoky Lapsang Souchong as their base, yet each produced a kombucha of utterly different character and temperament. As Kiwon had once said, once the basics are mastered, fermentation ultimately leads to a sensory expression of one’s own aesthetic.

“People never enjoy a fermented drink alone” – fermenting alone, yet drinking together. In sipping kombucha, we are also tasting the maker’s aesthetics and preferences; kombucha becomes a gustatory medium through which to reach another person. We open ourselves to one another through the exchange of microbes, trading terroir, emotion, and history. And tracing the origins of a fermentation seems, in the end, to become a tracing of the self. Time brews kombucha, and brews us. Why did this bottle earn the widest accord of praise? Why is that other bottle a particular friend’s tongue-peak favourite? As an object, kombucha – how is it made? And as a subject, this “I” – how am I constructed? Between public and private, subjective and objective, we experience overflow and confluence.

And that selected “champion” is our final, wordless accord – yes, we still believe in the phrase “seek common ground while preserving differences.” In a world ever more polarised and combative, we gather round a single table and, through kombucha, carry out a practical experiment in finding common ground amid difference. In sharing, exchanging, and talking, this microbial “blockchain” grows and multiplies, enacting the ideal of “decentralisation.”

I brought kombucha to the Foodthink office, where it became a regular post-lunch drink. There, among colleagues, we hatched the idea of a kombucha-themed sharing event, formally inviting Shuyu and Kiwon to share their fermentation story with the public.

While designing the event poster, Shuyu casually pointed at a small glass ornament on the desk engraved with the characters for “happy”: “Let’s call it ‘Happy Microbes’.” So simple, and yet so apt – a microbial community truly did bring us joy in our senses, our emotions, our social lives. In time, that logo was carried forward and kept, becoming the official name of their fermentation studio.

That day, before the sharing event officially began, the friends from “Happy Microbes” brought along an armful of recent ferments in jars and bottles, and held an informal tasting among ourselves first. This time, Xiaochao from Foodthink – a complete novice – walked away with the final prize. In the unpredictable story of fermentation, there is always the surprise of a “wild ferment” stealing the show. As for the leftover culture, once the sharing event ended, audience members who had brought their own glass containers adopted it and carried it home.

What stayed with me most was an elderly woman at the event who cried out the old name – “Sea Treasure.” When she was a child, the elders in her family had grown it and drunk it. Those days, the hutongs of Beijing hummed with the culture-keeping craze, drifting lane by lane, home by home; for a while it was riotous – almost every courtyard held a few “living” glass jars. Back then, in the public memory of the 1980s, “Black Tea Fungus” was the folk-science myth that succeeded the “chicken-blood injection” fad – a “cure for every ailment,” a fevered, superstitious pursuit of bodily function. And nearly forty years later, still in Beijing’s hutongs, this fermentation relay spreading among urban youth feels closer to a disinterested experiment in gustatory aesthetics. It has become a more postmodern need: free-floating, atom-like, we crave connection, react and coalesce; we seek re-enchantment, and amid all the “climate changes” around us, we search for and balance our own small climates, small ecologies, small universes.

V. Diaspora and Reinvigoration

From 2020 on, friends began leaving Beijing one by one. By the end of 2021, I too departed in haste, returning to my hometown’s small town. We, too, had begun to scatter. And kombucha travelled with the scattering: its origins in the Bohai Sea coast, swept into foreign lands amid the upheavals of the early twentieth century; becoming the health secret of longevity villages in the Soviet-era Caucasus; then carried to the island nation in the East by a Japanese Russian-language teacher on a trip to the Soviet Union; and in recent years spreading across Europe and the Americas, a subcultural favourite among “Post-Pasteurians.”

Along the way, kombucha made several returns to the mainland. During the culture-keeping boom of the 1980s, a series of related books was published: demystifying the principles of fermentation, cataloguing its benefits, listing folk cases… In passing remarks, they even glimpsed hazy traces of its presence in the early Republic era and after the War of Resistance.

What became, then, of those once-popular “Sea Treasures” of the 1980s? Perhaps the accelerating spring breeze of Reform and Opening brought the multiplication of wealth and the fermentation of consumerism, and we entered a new myth. Kombucha in China has gone through cycles of vogue, forgetting, return, and vogue again – its losses and triumphs riding the climate of the times, rising and falling with them.

In the spring of 2022, having settled into small-town life, I took the starter culture from the fridge – the one I had brought back from Beijing. After months of cold storage, they had grown terribly weak: the liquid clear and still, the pellicle sunk silent to the bottom of the jar.

We began a difficult re-adaptation together – I, confronting my native environment; they, meeting an entirely new place with barely perceptible vitality. Fermentation turned hesitant and sealed; the liquid seemed to stall, time nearly congealed, and my senses lost all connection with it. Two weeks later, at last, a wispy bloom surfaced in the liquid; bubbles rose, slow and tentative; the familiar sweet-and-sour fragrance overflowed the air once more. Through round after round of tea-sugar water refreshment and care, the colony reinvigorated, drew itself back together, and knit into a fresh pellicle.

The first jar fit to drink matured during the sudden April “silence”. This time, I shared the cup with my mother. From the residential compound, she had gathered bitter greens and pokeweed. With foraging and fermenting, we weathered the chaos and alarm of that spring day together.

After that, I helped friends in Beijing adopt starter cultures remotely, only to find it had turned into a lockdown relay – a culture ready to go out the door, and the compound would suddenly throw up barriers; by the time it finally reached the handoff point, the adopter was already under home isolation. Can the microorganisms in a jar perceive what kind of tsunami and terror another kind of microorganism is unleashing in the outside world? Kombucha was “non-essential”, yet we stubbornly maintained our fermentations and never gave up sharing with others. Through those days of isolation and silence, kombucha connected us to people, to faraway terroirs. Where the body cannot reach, let taste touch it; we resisted silence with the vitality of living things and, within fermentation, achieved a flowing freedom. Were we truly retreating to the last line? And so this tiny fermentation jar became our last territory – unable to partake in grand narratives, we actively constructed the smallest possible unit.

VI. Reunion

In September 2022, I returned to Beijing and walked into the little space by the Drum Tower – by now, Happy Lab. As in the summer of 2020, this was another reunion long overdue; yet it carried the same ease and ordinariness as the day I first tasted kombucha. We shared good food, fine tea, and idle talk of the world and each other’s affairs. Demolition and relocation works had already begun around the hutong by the Drum Tower, and the ruins were closing in. Nestled in a courtyard ringed by rubble and “silence”, Happy Lab pressed on with its fermentation experiments, and Kiwon’s records grew thicker, layer upon layer, like a pellicle. They shared kombucha in more public spaces, turned the old “tasting board game” into flavour-score cards, and launched small-scale paid sharing – posting kombucha to places near and far, drawing more friends into the dialogue with it: waiting for it to mature, tasting its flavour, retaining the right and the possibility of keeping a starter culture and brewing it themselves.

But there is no quiet desk in this world, nor any fermentation that stands alone. One lockdown after another brought a loss of microbial control – at one point, because the bottling materials were delayed, kombucha that could not be harvested in time was finally poured into a sink.

This post-meal kombucha was their recently opened ancient-tree ripe Pu’er; its mellow richness and velvety depth offered yet another wholly new experience and height. Kiwon once likened “tea” to a musical score – whether one steeps it or ferments it, the act is “performance”, and each person has their own way of playing. They are plainly ever more accomplished performers. Their patient, meticulous textual records serve as each jar’s identity code and taste-memory, offering space for calibration and reflection in future ferments. As they had always believed, the vast expanse of Chinese tea holds infinite possibility; they had carved out their own style and path, pressing ever deeper.

They are my genius friends – amid all the uncertainties in and around the jar, in the macro and the micro, they hold a self-assured, unwavering anchor, pressing steadily forward.

I often wish life could be like a perfectly fermented jar of kombucha – sweet-and-sour in balance, full of flavour, dense with bubbles, long in aftertaste. But what makes a fermentation “perfect”? Life cannot be wholly controlled. I cannot give these microorganisms a stable environment any more than I can give myself one. I have endured fermentations gone awry: their bitterness, their cloying sweetness, their sharpness, or the meddling of stray microbes. Tracing them back to root, they all stem from a rupture in the colony, an imbalance in the ecology – a single organism growing over-large while the commonwealth collapses. In the end, though, one simply lifts the lid and starts again: so long as you keep a starter culture, you keep a possibility.

Amid decay, turning points and new life brew. In the loss of control and confusion of living, we ferment out our own quality and thread; amid rot and entanglement, we renew and layer new selves upon ourselves, endlessly. Growth, too, is a state of fermentation – and time is its vessel. Complexity and multiplicity make flavour; the ideal of seeking truth can become nourishment.

The mentors, true friends, and dear family I have met in this life are those who keep a starter culture for me. They have taught me: keep practising, keep recording, keep reflecting. Only practice sustains vitality. Only recording guards against forgetting. Only reflection enables repair and forward motion.

So, I have rambled long enough. This piece is, for the past three years, the record and reflection I have fermented about kombucha. As for the story of these microorganisms: keep it updated, keep it fermenting, keep it open to share.

Notes and References

Neither Raw Nor Cooked: A Cultural History of Fermented Food, [French] Marie-Claire Frédéric, trans. Leng Biying, SDX Joint Publishing Company, 1st ed., Beijing, June 2020 Black Tea Fungus for Health and Longevity, compiled by Food Technology Magazine, Industry and Commerce Publishing House, 1st ed., Beijing, July 1981

Scientific Analysis of Black Tea Fungus, research by Masayoshi Sakamoto (DSc, Japan) and Watanabe Zhongsan (MD, Japan); edited by Bai Zhenhua

When a Stanford Astronomer and a Normal University Designer Made Kombucha Together – Heimi Chat Room https://www.xiaoyuzhoufm.com/episode/63b8273cda83c49d996a5dcd?s=eyJ1IjogIjYwZDVjMDk5ZTBmNWU3MjNiYmM1ODIyMSJ9

“Research Progress on the Sensory Quality and Related Chemical Components of Kombucha”, Tian Wenxin, Shen Jingjing, Dang Hui, Bu Xianpan, Tang Dejian, Zhang Baoshan, Zhao Yu, Science and Technology of Food Industry, Vol. 43, No. 24, December 2022

Foodthink author

Zhang Xiaoshu

Artist, graduated from Nanjing University of the Arts in 2016. Born in a small village by the river, raised beside a factory on the city’s outskirts, planning to move to the coast. Life is still in a state of wild fermentation.