A beginner's guide to fermented foods

Did you know that fermented foods can benefit your digestion, microbial diversity, inflammation levels, disease risk and even your mental health? It’s true! Fermented foods have been included in cultures and diets around the world for thousands of years, with evidence of fermentation practices dating as far back as 9000 years.¹

Still popular in Asia² and Northern and East Europe, many of these traditional foods are still included in modern diets, such as natto (a popular dish in Japan made from fermented soybeans), to surströmming (a fermented fish dish from Sweden), and of course kefir!

Why are fermented foods important?

One of the best ways to get more beneficial bugs into your body is by eating fermented foods. They boost nutrient absorption from food and aid with digestion. They also increase the variety of bugs that live in your gut who are constantly looking out for you!³ The benefits of fermented food range from helping to reduce inflammation⁴ to regulating blood pressure.⁵

What about fermented plant foods?

Although dairy products are a well-known source of probiotics, fermented plant-based foods also provide beneficial probiotics, particularly lactic acid bacteria (LAB). The primary LAB found in fermented plant foods include species from the genera Lactobacillus, Leuconostoc, and Pediococcus. The lactic acid bacteria help convert sugars into lactic acid, acetic acid and CO2. Those antimicrobial compounds help fight off pathogens, the ‘bad bugs’. These harmful microbes can contribute to bloating, tummy pain, and other digestive discomforts.

How do I get started?

With the growing popularity of fermented foods, many options are now widely available in supermarkets and health food stores, including vegan and gluten-free versions. If you’re new to fermented foods, getting started can feel overwhelming. A great approach is to break them down into different levels, helping you ease in based on your personal taste preferences and digestive sensitivity.

1. Easy entry-level: sourdough & tempeh

If you’re apprehensive about where to start or what to expect, then this is a good place to begin. These foods can be easily introduced into your diet and don’t have the fizzy taste that is often associated with fermented foods. As they’re not as strong, this is an ideal starting point for people who have a sensitive system or prone to IBS and bloating.

Sourdough

With artisanal bakeries and home baking on the rise, sourdough bread has recently gained popularity. It is made by mixing flour and water together and leaving it to sit at room temperature – this is known as the ‘starter’, and it gives it its flavour and fermented element.

Bacteria and yeasts naturally present in the flour, air, and surrounding environment feed on the mixture, triggering fermentation. This process not only allows the dough to rise but also gives sourdough its characteristic open-crumb texture.

Besides being rich in Lactobacillus species⁶, sourdough may have a lower glycaemic index (GI) than standard bread due to its slow fermentation. This means a more gradual rise in blood sugar levels, making it a potentially better option for people with diabetes or prediabetic people.

Tempeh

Originating from Indonesia, tempeh is made from fermented soybeans. Similar to tofu in taste and appearance, it has a slightly more dense, crumbly ‘meatier’ texture than tofu and a higher protein level. This makes it a good meat alternative for vegetarians and vegans. It contains vitamin B12 and is a complete source of protein, which means it has all nine essential amino acids your body needs to maintain healthy bones and muscles.

It has a fairly neutral flavour, so it takes on other flavours well, such as marinades and sauces, and can easily be added to curries, stir fry, or grilled and added to sandwiches. Try Saskia’s Super-Speedy Miso and Tempeh Stir-fry!

2. Mid level: kombucha & miso paste

This is the level for people who have a little more experience with fermented foods, so know what to expect and don’t mind a little bit of tanginess!

Kombucha

Believed to have originated in China before spreading to Russia and Eastern Europe in the early 20th century. Kombucha is a fermented tea made from tea, sugar, and a bacterial culture known as a SCOBY (symbiotic colony of bacteria and yeast). While traditionally brewed with black tea, green tea can also be used for a milder flavour. The SCOBY is added to sweetened tea, kickstarting the fermentation process. During this process, the yeast converts sugar into alcohol, producing carbon dioxide bubbles that give kombucha its signature fizz. Meanwhile, bacteria break down most of the alcohol into organic acids, including acetic, gluconic, and glucuronic acid.

Evidence shows acetic acid can inhibit certain pathogens commonly found in the gut⁷, while gluconic and glucuronic acid have been proven to increase Bifidobacterium levels⁸, and have liver detoxing properties.⁹

Miso paste

Known mainly for its use in miso soup, miso paste is made from fermented soybeans and is used extensively in Japanese and Asian cooking. It is made by combining soybeans, salt, and koji (a type of fungus cultivated on rice and other grains) and allowing it to age for months or sometimes even years. Similar to sourdough ‘starter’, koji appears in countless East Asian fermentation practices and is the starter used to ferment miso, soy sauce, sake and rice vinegar.

Miso is a versatile ingredient that can be used in a variety of dishes, from traditional miso soup to glazes for fish or noodles when combined with garlic and ginger. It can also be mixed with butter to create an umami-rich dressing for vegetables.

Miso paste typically comes in three colours – white, yellow, and red/brown. Because miso is a fermented product, it can be stopped at different stages of fermentation. The longer it ferments, the darker its colour and the deeper its umami flavour.

Shiro miso (white) is the mildest and sweetest variety, made with a high proportion of rice.
Shinshu miso (yellow) is an all-rounder with a slightly deeper flavour due to a longer fermentation time.
Aka miso (red/brown) is the richest and most intense, making it ideal for soups and stews – a little goes a long way, as its flavour can be quite strong.

3. Top tier level: kefir, kimchi & sauerkraut

These are the heavyweights of the fermented food world – the vinegary, tangy foods that pack a punch of probiotic goodness and flavour. If you’re a fan of zesty, tarty flavours, this one is for you. While their bold taste can be intense at first, they offer a higher reward in terms of gut health benefits, and many people find they acquire a taste for them over time!

Kefir

Our personal favourite! Kefir is a fermented milk drink packed with live, active cultures. It originates from the Black Caucasus Mountains of Russia, where the inhabitants were known for their longevity and good health. Over time, kefir spread across the globe, becoming one of the most popular probiotic drinks available.

The best kefir comes from goat’s milk and real grains. It’s best enjoyed unflavoured, as sugar and sweeteners can harm the good bugs. Kefir has a tart, tangy taste – think fizzy feta! If the flavour is too strong, try blending it into a smoothie with fruit or a touch of 100% stevia for a delicious twist.

For our award-winning kefir, we start with fresh, lightly pasteurised goat’s milk. The milk is then left to ferment with the grains before being strained and bottled. We never re-pasteurise our products, ensuring the kefir you receive is live, active, and packed with beneficial bacteria. What makes kefir unique is its synergistic combination of multiple strains of live bacteria, which thrive together in their own natural environment, creating a powerful probiotic drink.

Kimchi

This popular Korean dish is traditionally made from napa cabbage or radishes, which are brined with salt to draw out excess water. The vegetables are then mixed with chilli paste and seasonings such as spring onions, fish sauce, garlic, ginger, and gochujang – the ingredient responsible for its spiciness and signature red colour.

Kimchi has a rich, complex flavour often described as sour, spicy, tangy, and umami. Its fermentation is driven by ‘wild cultures’ of bacteria naturally present on the vegetables, creating its distinctive taste and probiotic benefits. If you’re committed to reducing food waste, try adding the brine from the kimchi to soy sauce, garlic and ginger to make a spicy, tangy marinade, or olive oil and honey for a sweet and sour salad dressing. Try Laura’s Kimchi & egg fried rice!

Sauerkraut

Typically thought of as a German dish, sauerkraut likely originated in China over 2000 years ago.¹⁰ Similar to kimchi, it is made by chopping cabbage and brining it to draw out water. Sauerkraut is rich in live bacteria that may help support a healthy gut microbiome by improving bacterial balance and strengthening the gut lining. A mix of lactic acid bacteria drives the fermentation process, which takes anywhere from 3 to 6 weeks. The longer it ferments, the more developed its flavour and probiotic content become.

As always, start slowly and gradually when introducing new foods or supplements into your diet. If you experience mild symptoms such as bloating or tummy pain, you may need to reduce your intake to a dose that suits you or take a break until symptoms subside.

If you’d like to learn more about fermented foods, check out What’s all the fuss about fermented foods? for more information.

Any questions? Contact one of our Nutritional Therapists via live chat, weekdays from 8 am to 8 pm.

A beginner’s guide to fermented foods