The Wanderer’s Journey: Yoghurt, Reimagined!

In contrast, there is naturally fermented yoghurt (sour milk) — a small amount of already fermented yoghurt (a starter culture) is added to fresh milk and left at room temperature. This provides the microorganisms in the starter with a suitable environment for growth and reproduction, as well as the necessary nutrients (the fats in the milk), allowing the milk to ferment into yoghurt.

To use a metaphor, the process is akin to an ancient army laying siege to a city and gradually assimilating its inhabitants. Different regions boast various types of yoghurt ‘crafted’ by different microorganisms; many fermentation enthusiasts take great pleasure in preserving or sharing ancient strains, yet the exact microbial composition of these cultures can no longer be precisely analysed.

Even yoghurt of the same variety and origin will see its colony types and activity levels affected by the different people, environments, and methods used to preserve it. Over time and through changing environments, these have evolved into resilient and inclusive little ecosystems, tirelessly preserving and evolving the flavours of the yoghurt.

Gradually, I began my own small journey of collecting strains, tending to our miniature microbial ‘pets’ alongside my colleagues at the studio. Throughout this process, I have realised that the joy of fermented foods lies far beyond the taste itself; it comes more from the exchanges and discussions shared with fellow fermentation enthusiasts.

While the small-scale exchange and transfer of strains are easy enough to imagine, preserving cultures over long periods and across vast distances is far more challenging. The fermentation of yoghurt is essentially the active growth of thermophilic lactic acid bacteria; by removing either the temperature or humidity factor, the microorganisms can be rendered inactive, allowing for long-term preservation. Even a child knows that leftover yoghurt must be put in the fridge—a method of lowering colony activity by altering the temperature. However, for dairy fermentation enthusiasts wishing to facilitate “culture exchanges” over a wider area, dehydrating the yoghurt—essentially altering the humidity—is often necessary for easier shipping.

Interestingly, in my search for various starters, I encountered a variety of “culture containers” born of grassroots ingenuity: some soaked cotton wool in yoghurt and then dehydrated it, while others sent yoghurt flakes in small sachets… these tiny organisms seem always to find their own quiet corners to dwell in, existing within the crevices of human industrial civilisation.

The most captivating of these is the story of Finnish immigrants from the last century. In The Art of Fermentation, Sandor Katz describes how Finnish immigrants would pour a small amount of Viili yoghurt onto a cloth, air-dry it, and roll it into their luggage to carry across the ocean to America, where it was then cultivated and allowed to take root:

“Finns refer to the starter or culture used for Viili as ‘seeds’. Even though Fan’s birthplace was Pragueburg, these ‘seeds’ travelled far from Finland with the Kinnuning family (and perhaps dozens of others). They would spread a small amount of fermented milk onto a clean handkerchief, dry it, roll it up, and carefully tuck it into their personal luggage before setting off. The seed, or the culture, was a way of carrying the past forward into a new land and a new life.”

On Christmas 2018, a friend bought some Viili in Finland and wanted to bring it back to Berlin for me, but was stopped by customs because liquids are not permitted on planes. Remembering the story I had told about Finnish yoghurt and fabric, they had a sudden flash of inspiration: they took a tissue, dipped it in a bit of yoghurt, and placed it in a small empty bottle. In this way, they effortlessly smuggled the tiny yoghurt microbes back to Berlin. After placing the tissue back into milk, the milk turned into Viili yoghurt within two days.

III.

The story of Finnish immigrants drew my attention to the medium of fabric. I began experimenting with air-drying ordinary yogurt onto fabric to use it as a starter culture.

In Germanic and Romance languages, the word ‘culture’ refers both to the cultivation of civilisation and the cultivation of bacterial colonies.

When we think of fabric, we can typically identify its cultural origins through the visual style of the weaving techniques or the printing and dyeing methods used. In this regard, fabric serves as a medium for expressing ‘culture’ in the civilisational sense.

In the story of the Finnish immigrants, however, fabric became a vessel for ‘culture’ in the literal sense—as a bacterial colony. This linguistic duality is quite playful, and it led me to consider how I might use fabric to simultaneously convey these various meanings of the word ‘culture’.

If applying yogurt to fabric and allowing it to dry is a process of transforming the cloth into a ‘medium’ or ‘container’, then could the yogurt—the ‘content’—be presented within that container in a way that is regularised or aestheticised?

If fabric serves as a carrier for yogurt cultures, could it be repurposed once its role in transportation is complete? I turned my attention to the thick, snowy-white yogurt—could this semi-liquid substance be used as a pigment to depict the very microorganisms it contains?

I selected three different yogurts from three distinct cultures: Viili from Finland, Matsoni from Georgia, and Filmjölk from Sweden. Each culture possesses striking textile traditions: Georgian geometric carpets, Finnish checked fabrics, Swedish Kurbits patterns…

Extracting the most representative visual elements from each culture, I designed three sets of graphic patterns for each yogurt. The fabric, acting as the container, was divided into 10x10cm squares. Using food-grade pigments and screen printing, I printed the negative space of the pattern and the name of the respective yogurt onto each square. I then applied the corresponding yogurt to fill the positive space of the pattern and left it to dry.

Each small square of fabric can be used to culture a small jar of the corresponding yogurt: simply dip a square of cloth into milk, cover the mouth of the jar with a paper towel or another breathable fabric, and place it in a warm environment. Within two days, the milk will transform into that specific yogurt, ready for a new round of fermentation. Once washed, the fabric—with the milk pigments removed, leaving only the screen-printed negative space—can be repurposed as the cover for the next batch, serving as a subtle reminder of the yogurt strain inside.

The Process

1. Screen printing: printing the negative space of the three yogurt patterns onto the fabric using food-grade pigments;

2. Sewing: overlocking the edges of the squares with a sewing machine, then carefully pulling out the threads between the stitches;

3. Applying the dairy products.

The way the textile was treated made it easy to cut the fabric used for the starter containers into small squares. Their lightness meant they could be tucked into any nearby corner; in this sense, the starter cultures possess an infinite potential for extension not only along the axis of time, but also across different spaces, wandering wherever people go.

I cut out these completed starter containers one by one to share with friends—some sent by post, others handed over in person. Supported by a piece of lightweight fabric, these tiny lactic acid bacteria completed their journey as wanderers.

Feedback from friends suggests that natural fermentation remains inherently unpredictable, and not every little vessel yielded a perfect result. However, as one friend put it—”it was all great fun”—and I believe that is precisely where the joy lies: in cultivating and swapping cultures, and savouring fermented foods in the rhythms of daily life.

The art piece “The Wanderer”, inspired by yoghurt fermentation as described above, will be exhibited at the “Ferment Your Life” festival market on 22 October. More tastings and sharing activities await your discovery on the day. This autumn, let’s “Ferment Your Life” together!

This article is reprinted with permission from the author’s blog