Surprising living foods you might already be eating

In recent years living fermented foods have become synonymous with kimchi, sauerkraut, kefir, kombucha and the like. But fermentation is used across the food industry to create thousands of everyday foods. For example, chocolate, bread, beer, wine, olives, coffee, some teas and more are all made with fermentation as part of their production. However, most if not all of these will have then gone through steps that involve killing off these beneficial microbes.

In the UK live fermented foods have mostly fallen out of our food culture, even though they've always been a part of it until relatively recently. Historians debate why this has happened, one theory is that these foods were always typically made at home by 'peasants' but as specialist artisan makers became more common it became unfashionable and 'beneath people' to make them at home, so the skills were largely lost. However, there are still many everyday foods which do contain live cultures that you might already be eating, which is what we're highlighting in our latest blog. So have a read and then surprise your mates next time you're at the pub with our living food facts!

Raw fruit and vegetables

We often amaze people at our workshops with the fact that all fruit and vegetables grown in the ground are covered in microbes (1)! Specifically for lacto-fermentation they're covered in lactic acid bacteria which, helpfully, is the group of bacteria responsible for making sauerkraut and kimchi (and many other ferments). This means that every time you eat raw fruit and veg you're getting some live microbes. However it's important to note that the amounts of these microbes will be much less than in fermented versions. This is because when we ferment food ingredients we're encouraging specific microbes to grow exponentially (i.e. a lot!). Another thing to bear in mind though is that any beneficial effects from the live microbes on raw produce is near impossible to differentiate from the nutritional benefits of eating them as they're also packed with fibre, polyphenols, vitamins and minerals.

Cottage cheese

Cottage cheese might not be the first food that comes to mind when you think of live cultures, but some brands actually do contain beneficial live bacteria. Traditionally, cottage cheese is made with lactic acid bacteria, which help ferment the milk and create its characteristic tangy flavour and creamy texture. While many commercial brands pasteurise their products after culturing (killing off the live bacteria), some still offer versions with active cultures, making them a sneaky source of gut-friendly bacteria. Working out which brands are living or not is tricky though; having reached out to a few we found out that Longley Farm cottage cheese (the first commercial cottage cheese makers in the UK) does contain lactic acid bacteria, but this fact isn't widely promoted by the company.

Sour cream & creme fraiche

Sour cream and crème fraîche are two other dairy ferments that can also sneak live bacteria into your diet. Both are made by fermenting cream with lactic acid bacteria, which thickens the texture and gives them their signature tang. While many commercial sour creams are also pasteurised after culturing, killing off the live bacteria, some brands still contain active cultures. Crème fraîche, which is higher in fat and less sour, is more likely to retain its live probiotics since it’s often less processed. However again it's not easy to work out which brands are alive and which aren't and even with our research we haven't got any to share with you unfortunately. But either way these are two dairy delights which are delicious to cook with so get experimenting anyway.

Yoghurt

Yoghurt is one of the most well-known and the best studied fermented foods, but as with the other dairy ferments not all brands will contain live cultures. Traditionally yoghurt is made by fermenting milk with specific bacterial strains like Lactobacillus and Bifidobacterium, developing a creamy texture and tangy flavour through this process. However, some commercial yoghurts are heat-treated after fermentation, which destroys the beneficial bacteria. To ensure you’re getting live cultures, look for labels that mention “live and active cultures" or make your own easily at home. One way to know if a brand is alive is to try and use it as a starter culture for making yoghurt at home. If it's alive you should be able to add it to heated then slightly cooled milk and when left it should thicken the milk due to fermentation.

Aged cheese

Hard aged cheeses like cheddar and parmesan will likely contain live microbes when you consume them. The balance of these microbes determines the flavours and textures of the end cheese and is finely tuned in commercial cheese production. However, the amounts of microbes still alive in these cheeses when you eat them will vary widely and depend on how they've been aged (the longer the more likely they are to start dying off) and how they've been stored. As with any of these fermented dairy products those made by artisanal producers are more likely to be made with traditional, microbe-encouraging techniques rather than industrial processes which focus instead on consistency and cost. This means that artisanal brands have the potential for greater amounts and diversity of microbes in the end product.

Salami

Salami might not seem like a living food, but traditional varieties rely on fermentation to develop flavour and texture. If you've ever seen images of salami during its fermentation step you'll often see a mould which develops of the outside, which helps to develop flavour. This step also helps create conditions for beneficial bacteria, such as Lactobacillus, to grow helping preserve the meat and create its unique flavour. Unlike heat-treated deli meats, properly fermented salami still contains live cultures when eaten. However, many mass-produced versions are pasteurised or contain added preservatives like nitrates which eliminate these beneficial microbes. So if you're looking for a living cured meat then you'd definitely want to go for artisanal or naturally fermented versions.

Gherkins

Most of the pickled cucumbers available in shops will either have been made using vinegar pickling, meaning a high amount of acid in the form of vinegar is used to preserve the cucs, or they've been pasteurised. We've found only a couple of live, fermented gherkins available in (mostly) niche shops. When we make gherkins at home we mostly use a combination of brining and vinegar pickling which allows the cucumbers to ferment in a controlled way to preserve the texture of the cucs and giving that signature vinegary taste we all love from gherkins!

Miso

Most misos that you can buy in supermarkets are unlikely to be living. This is because pasteurisation is a very common technique to extend the shelf-life of foods and maintain stability of products so that they can be kept at room temperature. Traditional misos are made by mixing cooked soybeans with salt, a little water and koji (a mould coated on rice) and leaving it to ferment for several weeks, months or years. Miso has a rich, umami powerful flavour and is amazing in marinades, soups, baked goods, sauces, noodles and salad dressings. Although mould is the main microbe in miso there will be other bacteria and yeasts within miso, giving a complex ecosystem of microbes. Learn more about miso and koji in our recent blog.

You can spot unpasteurised versions as they'll often be stored in the fridge or state on the label that's how they require storing. Smaller, artisanal brands also tend to be unpasteurised as they recognise the benefits of maintaining the living ecosystem. We love Umami Chef, a soya-free miso brand based in the UK.

Vinegars

Living vinegars are raw, unpasteurised vinegars that still contain the “mother”—a colony of beneficial bacteria and yeast that aids in fermentation. Live apple cider vinegar is probably the most well-known living vinegar in the UK. In contrast, non-living vinegars - such as most commercially produced malt, white, balsamic, and wine vinegars - are typically pasteurised and filtered, removing the beneficial microbes. If you’re looking for a vinegar with gut-friendly properties, opt for raw, unfiltered varieties labeled with “the mother” and shake the bottle before use to distribute the beneficial cultures.

Why consume living foods at all?

Many of the bacteria in fermented foods are what can be called 'probiotic-like' and are associated with good digestive health and other benefits. However, most traditional fermented foods have not been studied in controlled trials for their health effects. In many cases, scientists have not characterised the types and amounts of microorganisms in different fermented foods and therefore can't test the microorganisms’ specific health benefits. It's worth bearing in mind that these products can sometimes be accompanied by claims related to the 'probiotic' benefit of these foods, which isn't actually legal unless the producer can back it up with a relevant authorised health or nutrition claim. Some fermented foods such as many commercial yoghurt products do contain added probiotics which are usually listed on the label and these confer a scientifically demonstrated health benefit. Nonetheless, fermentation-associated microbes that have not reached the status of ‘probiotic’ may share many of the traits of known probiotic organisms.

We hope this gives you some reassurance that you don't have to buy expensive live fermented foods to help add in live cultures into your diet. And if you're looking for a cost effective way to up your intake then we wholeheartedly recommend making them at home! Sauerkraut is a great place to start, as you need little more than a cabbage, salt, chopping board, knife, bowl and re-used jar. For those looking for a bit of extra guidance, check out our blog for recipes for making different live foods at home and our workshops here we offer online courses or in-person classes on fermentation, incorporating our skills as nutritionists throughout.

REFERENCES

(1) Wicaksono WA et al. (2023). The edible plant microbiome: evidence for the occurrence of fruit and vegetable bacteria in the human gut. Gut Microbes. 15(2):2258565. doi: 10.1080/19490976.2023.2258565.