World Ferment Day - 1st February

January 28, 2026

To mark World Ferment Day, we sit down with nutritionist and long-time CULTJAR collaborator Jo Webster to talk about all things fermentation - from flavour and function to why these ancient techniques matter more than ever.

We have previously collaborated with Jo on one of our most distinctive recipes: Jerusalem Artichoke and Horseradish - a ferment that brings together bold flavour with gut-supporting benefits.

We’re very lucky to have Jo living on our doorstep. A nutritionist, medical herbalist, fermentologist and biophilist, Jo has dedicated more than 20 years to researching, teaching and championing fermentation and its impact on human health.

Like us, Jo is deeply passionate about the natural power of fermentation - and that passion led her to create World Ferment Day, encouraging us to take action by making, buying and tasting ferments, rather than simply talking about their benefits.

Why did you create World Ferment Day? Why does it matter now?

The aim of World Ferment Day is less about words and more about action. As a scientist, I like many others, have talked A LOT about the enormous functional potential of these foods in a world where we are understanding more and more about the role of gut microbiota in health and in a world where the levels of chronic disease continue to rise. Ferments are delicious, nutritious, complex, diverse. They are made using one of the most ancient of food technologies. They deliver microbial nutrients and live and inactivated microbes in a form humans have been consuming for millennia. They are mostly cheap and very easy to make.
Despite all of this, in some cultures where fermented foods and drinks have a long history of use, there is a move away from these foods towards a more Westernised diet. And in cultures (like us in the UK) where lactoferments have not been a significant part of our food culture, we would likely benefit from eating more of them. So World Ferment Day is about eating and drinking ferments, not talking. It is about growing an initiative and a community that supports buying or making a ferment and tasting it. We need more focus on foundational health practices that we can enjoy doing for the rest of our lives and that we know, if we do incorporate them, are very likely to positively influence health. Ferments fit these criteria.

With the introduction of World Ferment Day, why is it important in your opinion, to spread the word about the benefits of fermented foods around the world?

The aim of World Ferment Day is less about words and more about action. As a scientist, I like many others, have talked A LOT about the enormous functional potential of these foods in a world where we are understanding more and more about the role of gut microbiota in health and in a world where the levels of chronic disease continue to rise. Ferments are delicious, nutritious, complex, diverse. They are made using one of the most ancient of food technologies. They deliver microbial nutrients and live and inactivated microbes in a form humans have been consuming for millennia. They are mostly cheap and very easy to make. Despite all of this, in some cultures where fermented foods and drinks have a long history of use, there is a move away from these foods towards a more Westernised diet. And in cultures (like us in the UK) where lactoferments have not been a significant part of our food culture, we would likely benefit from eating more of them. So World Ferment Day is about eating and drinking ferments, not talking. It is about growing an initiative and a community that supports buying or making a ferment and tasting it. We need more focus on foundational health practices that we can enjoy doing for the rest of our lives and that we know, if we do incorporate them, are very likely to positively influence health. Ferments fit these criteria.

Which countries in particular are renowned for using ferments as part of their national cuisine?

All countries use fermentation in their cuisine as far as I know. It is one of the oldest and most universal food technologies. I visited South Korea in 2025 for my research into kimchi. I witnessed how fermented foods and drinks; from kimchi to gochujang (spicy fermented paste) to doenjang (soy bean fermented paste) and more, are an embedded part of their culture, From China to Japan, Taiwan, Poland, Germany, Scandinavia, Russia, India, Africa, to the Inuits in the Arctic and subarctic regions of North America, fermented foods are hiding in plain sight.

For those new to fermented foods, it can seem quite a lot to start with. How would you recommend introducing ferments into their diet. Is it something that we should be aiming to include on a daily basis going forward?

Aside from fermented vegetables, what other types of ferments would you recommend including into your diet? The aim is to incorporate these foods and drinks for the long term. I recommend starting with the type of ferment that appeals to you most; that feels like the easiest win. Whether this is fermented veg., milk kefir, water kefir or some spicy sriracha, or maybe kombucha in place of a gin and tonic on a Friday night. Start with one and incorporate it on a regular basis. Once that is established, see what else you can add in. Over time, this won’t be a prescriptive thing that you feel you “have” to do daily. These foods and drinks become a normal part of your diet that you miss if they aren’t there. I have milk kefir most mornings. I had some kimchi with my dinner this evening. Over time, reaching for these foods and drinks becomes a normal part of your food repertoire. This is what we are aiming for, because it is health behaviour changes that are sustainable for the long term that really can, over time, improve healthspan.