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  • Jeanne Kessira

The Virtues of Fermentation

There’s something at once self-affirming and exhilarating about creating a home for something wild to grow and thrive. Self-affirming because it is no insignificant feat. That particular sense of pride we feel when engaging in the act of creation is all the more amplified when it involves something that is alive; exhilarating because of the potential for chaos that is inherent in a wild ecosystem. We run the risk of causing death to our live projects, and are constantly teetering the line between the parallel universes of fermentation and rot. It is the first point that drew me to study fermentation and then teach it, and the second that keeps me hooked years on.

Fermentation is a metabolic process that occurs with or without us; our role as fermenters is to create a hospitable environment for the beneficial bacteria to thrive whilst keeping the toxic ones at bay - effectively guiding our foods away from rot and decay. We try our best to encourage the growth of good cultures by maintaining optimal conditions through temperature regulation, controlled exposure to oxygen and providing them with the right food to grow. But ultimately, these cultures are live critters that would exist and metabolise without our intervention.

Fermenting is a constant balancing act. It is not an exercise of domination, rather symbiotic cohabitation. There’s certainly a level of technical knowledge necessary for successful fermentation, but it is also intuition-based. I like to think of the science and the feeling of fermentation as its hard and soft skills, both necessary in adequate doses.

How we ferment

If we imagined an “approaches-to-fermentation” spectrum, there would be two dominant, polar opposite ends.

The hyper-technical approach relies on science, measuring and controlling each and every factor under lab-like scrutiny. This approach prioritises accuracy and safety and generally produces consistent results, making it appropriate for large-scale production. It is this methodical approach, for example, that was central to the industrialisation of Cheddar cheese-making (amongst countless others) and spurred research and experiments to understand the role of factors like temperature and acidity on the production of one of England’s most loved cheeses. Similarly, recent scientific research into the beneficial impacts of probiotics - the live microbes present in fermented foods - on human health is just hitting “the tip of the iceberg” merging a traditionally artisanal process with modern medicine.

Then there is the wild approach - the way our ancestors fermented, according to an intuition developed from consistent practice and knowledge sharing over time. Instead of relying on special equipment and metrics, our senses are our primary tools. Whilst this approach can be more volatile in terms of result, it is a style that is more in tune with seasonality and changing contexts. Variety too has its appeal, and the mercurial results we obtain from this style of fermentation allows us to train our intuition in the process.

It is entirely possible to bridge both styles to both regulate ambient temperature and measure pH levels whilst also perceiving the evolution of our ferments through careful observation: smelling, feeling, and frequent taste-testing.

white and black ceramic bowl filled with traditional kimchi against a wooden table as background

On care

Regardless of fermentation style, there’s no doubt that fermentation is an act of care.

It is care for the ferment and the self. There is great emotional satisfaction in forming that relationship with something alive, nurturing it, watching it thrive. In return for this care, consuming fermented foods can benefit us internally. The live bacterial cultures we consume contribute to our gut microbiome, a fancy term for the ecosystem of microorganisms that live and survive in our guts.

Much like with agriculture and in ecological communities, a diverse population of organisms - be they plants, animals, or bacterias and yeasts - ensures survival by maintaining balance and encouraging resilience. In the modern fermenter’s bible, The Art of Fermentation, Sandor Ellix Katz shares that for centuries, cultures across the globe have incorporated fermented foods in their diets believing that they “are special foods, able to nourish us deeply and help keep us healthy”. Fermented foods come in varied forms, and each of those products will have a unique combination of microorganisms that bring diversity to the gut microbiome, improving digestion and, as numerous preliminary studies show, boosting immunity and overall health.

Engaging in fermentation is an act of self-preservation, on microbial and human level. The bacteria create specific acidic compounds that they can survive in but which also keep toxic strains away. Similarly, we develop our fermenting and cooking skills in order to feed ourselves, one of the most fundamental acts we can take towards caring for ourselves and becoming self-sufficient. When you are able to make your own food from raw ingredients, you cut out the middle men, along with the material resources, cost, time, and transport it would take to produce. You can provide your body with the fuel it needs to thrive and have it taste as you like, whenever and however you want it.

On sharing

Fermentation is also a shared act. It has been part of global culinary cultures for millennia. Knowledge and technique are transmitted across generations and borders, adapting to new environments as necessary. And because it is at once technical and intuitive, it easily turns into something you partake in with others, that exchange of learning and teaching in constant flow between fermenters.

The contemporary revival of fermentation, especially in urban spaces where people are largely disconnected from their food sources, has inspired collectives and associations to grow, aimed at building community but also much more.

These networks that champion fermentation practices form part of a wider-spread movement to revive (and adapt) pre-industrial food production systems in an effort to combat the ills of industrialisation. From environmental practices that have ravaged the earth, its soil, and natural resources, to geo-political agreements that have only worsened existing inequalities, to a general detachment from and thus obscuring of where our food comes from, the metaphorical rotting of our contemporary food system stands in clear contrast to the benefits, relationships, and life that fermentation as a practice nurtures.

Engaging in the act of fermentation is a direct act of shared protest. One that is also delicious to partake in, for it is often done in good company and with the ultimate goal of creating gastronomical pleasure. Among their quantifiable virtues, fermented foods also happen to be delicious.

And as above, so below - the critters behind fermentation are themselves part of communities, working together with the shared objective of survival. Just as the cultures of fermentation across the globe work to perpetuate the craft, so do the different bacterial cultures work together to ferment. The relationship between ferment and fermenter is at once symbiotic and mirrored; one supports the other’s life journey, the very same journey it is on itself.

glass jars filled with different fermented fruit and vegetables stacked on top of one another in a classroom, students are in the background tinkering with their concoctions

On being alive

And finally, fermentation is a live act, meaning it is in perpetual development.

The question I get most often during my fermentation courses is “when is it ready?”, but there is no end-of-the-journey climax when it comes to fermentation. It’s more realistic to consider the entire scope of your ferment’s life, going through various stages of maturation and providing gifts of sustenance and lessons in patience along the way. There’s the initial stage when it is imperceptibly fermented and really just appears wilted; the stage when it gets fizzy-fermented and swells with gas; the stage where physical activity slows and flavour intensifies as it becomes tangy-fermented; and the stage where it gets F U N K Y (in all capitals) as it sits in its own unique pool of microbes.

The only sure measurement of “readiness” is taste. But not the taste of perfection - readiness is subject to your desire. You should regularly taste your ferment throughout its life cycle to track its progress. I like my kimchi fizzy, a result of the carbon dioxide released in the early stages of fermentation, so I make sure to eat plenty of it during that first week. After that, I let it continue to do its thing until it’s pleasantly acidic. At this stage, it is moved into the fridge to slow down bacterial activity–someone with a sensitivity to tang may fridge it much sooner. Bacterial cultures evolve throughout the process, all the more reason to regularly enjoy your ferment in order to reap the full range of diversity it has to offer you. Each batch truly has a life of its own.

And as with any endeavour, and especially a live one, you are constantly running the risk of something going off. Pathogens, the antithesis to our beneficial bacteria and yeasts, are always lurking on the horizon. It is this fear of the unknown that industrial bodies of science and production sought to eradicate in the name of “purification” and “sanitisation” - by implementing hyper mechanised processes that sterilised natural microbial strains only to reintroduce laboratory-made versions of them as additives, effectively killing life.

They also removed human involvement, and we fell out of touch with our fermentation senses, what it meant to preserve our own harvests in preparation for less bountiful seasons, and the satisfaction of contributing our personal microbes to our ferments. The absence of touch was meant to limit rot, but introduced a dystopian version of it instead. As we became disconnected, it became easier to be convinced that someone else knew best what was good for our bodies and how we should take care of ourselves. Our power over our food and our bodies relinquished to food industrialists who in turn reaped the financial benefits of our dependence.

Fermenting is a gentle act of rebellion, rooted in care and community. It is reclaiming our sovereignty, our relationships, our health, our lives.

On connection

In a technology-dominated, post-pandemic world, it seems we’re constantly on the lookout for how to foster more “connection” in our lives - connection with others but also with the natural world. But speaking in terms that dissociates us from our environment isn’t helpful; we are all conscious living beings, sharing the same space and evolving as we do.

The brilliant Vittles addresses that conversation in a newsletter last spring regarding regenerative farming, bringing up questions on how we can rethink our place in relation to our environment. An open letter written by ten Indigenous leaders in the United States sums up a common Western discourse that “Nature is viewed as separate, outside, ideal, perfect. Human beings must practice “biomimicry” (the mimicking of life) because we exist outside of the life of Nature.” Instead, these authors compel us to think of “our role AS nature.”

Nature is not straightforward, nor can it be submitted to control - but by rethinking our conversations around the relationship we have with it and with our food systems, we can slowly begin to rebuild a more balanced, alive alternative. Fermentation is no silver bullet, but it is part of the journey to achieve that new structure.

Connection does not need to be found; it is inherently there and can happen via the most mundane of acts, in the cadre of the everyday, sometimes just between our fingers and some wilted slices of cabbage.


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It doesn't have to be like this, Sebastian Delamothe

Jeanne is a food anthropologist, pastry chef, fermenter, and culinary teacher. She’s worked in various sectors of the food industry since coming to London six years ago, most of which have involved working with doughs and/or fermented goods (and then picking up a pen to write about it every so often). She’s currently working for hospitality service platform Countertalk, and teaching at the Bread Ahead Baking School.

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