Everything You Need to Know About Fermentation

Fermentation is an age-old practice that makes food more nutritious and flavourful. Read on to discover how fermented foods—from sauerkraut to kefir—can elevate your meals and improve your well-being.

Long before refrigerators became a kitchen staple, civilizations around the world relied on fermentation to preserve food. Archaeological findings reveal that our prehistoric ancestors used fermentation not only to make alcoholic drinks but also to extend the shelf life of vegetables and grains—and even to make bread! This technique is deeply rooted in culinary traditions worldwide, giving rise to signature dishes like South Korean kimchi, Japanese miso, and Eastern European sauerkraut.

During fermentation, bacteria, yeast and moulds convert sugars and starches, lowering a food’s pH and creating an acidic environment that inhibits the proliferation of harmful microorganisms, prolongs freshness, and enhances flavour and texture. One of fermentation’s greatest benefits is that it breaks down sugars with enzymes, making food easier to digest. For example, milk-based kefir has a significantly reduced lactose content due to fermentation, making it easier to digest for those who are lactose intolerant. Similarly, fermenting cabbage into sauerkraut or grains into sourdough bread lowers complex sugar levels, which is beneficial for people who have trouble digesting fructans.

Fermentation doesn’t just help digestion—it also reduces antinutrients that can block the absorption of essential nutrients like iron and zinc. By breaking down substances like phytates in grains, fermented foods significantly improves the body’s ability to absorb vitamins and minerals.

Fermented foods also promote a healthy gut microbiota by stimulating the production of probiotics, the beneficial bacteria that support gut health. Having a rich and diverse microbiota helps protect against infections and supports mental health through the gut–brain connection, which is the direct link between the digestive system and the brain.

However, not all fermented foods are rich in probiotics, as it depends on the strain of bacteria used in the fermentation process and whether it can survive digestion. And some practices, such as pasteurization or cooking, can destroy these beneficial bacteria.

There’s no one-size-fits-all approach to incorporating fermented foods into your daily diet, but it’s best to introduce them gradually. If you experience bloating, try adjusting the amount, frequency or type of fermented food you eat. Here are some of our favourite easy-to-integrate options :

This German specialty, sauerkraut, made from finely sliced cabbage fermented with salt, is high in fibre and adds a satisfying crunch to sandwiches and salads.

A staple in traditional Korean cuisine, kimchi is made from nappa cabbage, daikon radish, carrots, onions, garlic and ginger, fermented and often seasoned with Korean chili pepper (gochugaru). It pairs well with poke bowls, salads and stir-fries.

Aside from cabbage, many vegetables—such as carrots, beets, cauliflower, green beans and radishes—can be fermented to boost their taste and nutritional value.

A refreshing alternative to soft drinks, this slightly fizzy drink is made from fermented sweet tea. To fully enjoy its probiotic benefits, choose unpasteurized versions. Remember that kombucha can contain small amounts of alcohol (from 1% to 8%).

A fermented milk drink with a tangy, yogurt-like taste, kefir can be enjoyed plain, flavoured with cocoa, cinnamon, or vanilla, or blended into smoothies and salad dressings.