Fermentation is when sugars convert to alcohols or acids, via the action of bacteria or yeasts. Fermented foods like kimchi have been shown to be good for the human gut microbiome. — FILEPIC
On a sunny Friday morning in Janda Baik, Pahang, a small group of men and women head out to harvest fruits and vegetables, picked fresh from the sprawling organic farm, A Little Farm on the Hill. These farm-fresh produce would then be used to make a range of fermented products.
The group is a diverse one – there is a mother-and-daughter keen to learn more about fermentation; a Japanese chef who wants to implement it at his restaurant; a mum hoping to utilise her surplus food waste; and even a young student interested in the intersection of food and agriculture.
After filling their baskets, the group heads to demo tables that have been set up and huddle excitedly around fermentation expert Rachel de Thample, listening in rapt attention as she explains how to ferment radish and torch ginger flower into a modern interpretation of kimchi.
“We’re going to be making kimchi today. All the vegetables will be rich in minerals and nutrients, especially because we’re picking them and putting them in the jar. So they’ll have have even higher good bacterial content, but also higher nutrients.
De Thample holds fermentation workshops all over the world and has personally noticed just how much her own health has improved from consuming fermented foods. — ABIRAMI DURAI/The Star
“And when you put them in the jar and ferment them, you actually increase that (nutrients) by up to 50% so you get more. So I love the fact that you can take something that’s already good for you and make it even better by extending its shelf life,” says de Thample.
De Thample is an award-winning author who runs fermentation workshops at River Cottage in Devon, United Kingdom. She has also written cookbooks like Less Meat, More Veg, Tonics & Teas and the River Cottage Fermentation Cookbook. A former chef, she previously worked in restaurants helmed by Marco Pierre White and Heston Blumenthal, to name a few.
She was in Malaysia a few weeks at the invitation of the owners of A Little Farm on the Hill – Lisa Ngan and Pete Teo – who collaborated with her to run a fermentation workshop.
Interest in fermentation is now at an all-time high – driven by both consumer demand as well as a more commercial landscape focused on expanding this market segment. In fact, according to the Good Food Institute’s State of the Industry: 2023 report, over 70% of investments in fermentation have occurred in the past three years and in 2023 alone, the number of fermentation companies grew by 16%.
There has also been a tandem interest in home fermentation – as demonstrated by de Thample’s workshop – which was fully booked out.
But first, what is fermentation?
Fermentation
Fermentation is what happens when sugars convert to alcohols or acids, via the action of bacteria and/or yeasts.
Organically grown vegetables have higher levels of good bacteria and this is heightened during the fermentation process. — ABIRAMI DURAI/The Star
According to de Thample, there are three types of fermentation: lactic acid, ethyl alcohol and acetic acid. All three yield the same result: a transformation into a sharp, sour dish.
“Fermentation will not happen without bacteria, yeast or mould. To kick start fermentation, you must either add live bacterial cultures to the raw materials you wish to ferment or encourage the bacteria and yeasts already present in the food to multiply by providing the right conditions.
“Some ferments need to be exposed to air (aerobic conditions) which leads to the creation of acetic acid as in the case of vinegar, kombucha and kefir. Other ferments, including pickles and alcoholic drinks, must be locked in an airtight vessel and starved of oxygen (anaerobic conditions) which creates ethanol and lactic acid.
“For lactic acid ferments, such as sauerkraut, kimchi and traditional Polish pickles, salt is crucial. Not only does salt help strengthen pectin present in vegetables, giving you a crispier pickle, it also raises the acidity and creates an environment that is antagonistic to harmful pathogens and bacteria such as botulism,” says de Thample.
Yoghurt is an example of a fermented product. — PIXABAY/Pexels
Examples of fermented foods include kimchi, sauerkraut, kombucha, yoghurt, kefir and fermented cheese.
Fermentation benefits
In the past, fermentation was often employed to make use of vegetable scraps or even as a means of extending the shelf life of vegetables during harsh winter months (as in the case of kimchi) but in the past century or so, the practice gradually faded out of favour with increased prosperity, a culture of wastage and a heightened propensity for processed foods.
But in the past eight years or so, there has been a resurgence of interest in fermentation, buoyed by increasing awareness of the health benefits of fermented foods.
“I’ve always been interested in health and how food can play a role. And after I had my son 18 years ago, I didn’t feel very well, my energy levels were low. And also when I moved to the UK, I developed psoriasis.
“So I went to see a nutritionist and I did a gut health test and found out I had no good bacteria in my gut. So the nutritionist was quite shocked and said, ‘You know, it’s unusual to have such a low diversity score.’ So she sort of told me to have lots of fermented foods.
De Thample says after she switched to eating more fermented foods, her gut diversity score went from 0 to 9. — ABIRAMI DURAI/The Star
“Initially, when you sort of want to build your gut microbiome back up, you also strip your diet back to really simple things, like mostly vegetables and simple proteins, no sugar, including fruit. So you have this more simple diet for about six weeks and then you start having lots of fermented food. I instantly felt better and my psoriasis went away too.
“And it’s kind of like nurturing, it’s kind of, you can look at your gut microbiome like a rain forest and eating foods like ferments that help support that new diversity and get it growing. And it was interesting, because I did a microbiome test about two years ago, and I hadn’t done one since the initial one.
“And then suddenly I went from like a 0 out of 10 diversity score to 9 out of 10. Just mostly through food, l am not taking supplements or anything. So I just thought, ‘Wow, food is very powerful!’” says de Thample.
De Thample’s own experience with fermented foods is not isolated. Science, data and research back these findings too. According to an article in Harvard Health, one of the biggest benefits of fermented foods comes from probiotics, which essentially means fermented food is easier to digest and promotes gut health.
Researchers from Standard University also discovered that a diet high in fermented foods boosts microbiome diversity and improves immune response (which is exactly what de Thample’s bodily response proved).
In the past, the human gut microbiome constantly renewed itself, largely because people were exposed to more bacteria and had a less processed diet. With the introduction of better hygiene and sanitation as well as antibiotics and a diet heavily influenced by ultra-processed foods – there have been massive changes to the human gut microbiome, which has also precipitated leaky gut syndrome.
“The study provides one of the first examples of how a simple change in diet (to fermented foods) can reproducibly remodel the microbiota across a cohort of healthy adults,” says Justin Sonnenburg, an associate professor of microbiology and immunology, who was part of the research study.
Fermentation isn’t highly technical, according to de Thample. In fact, she often ferments whatever vegetables she has with salt. — WENDY WEI/Pexels
The study also showed that four types of immune cells showed less activation when participants were fed fermented foods, essentially boosting immunity levels.
Fermented foods may also support heart health and lower risk of heart disease as well as potentially aid in weight loss, according to Jo Williams, a registered nutritionist in an article in BBC Good Food.
Fermentation also helps increase the health potential of certain ingredients. For example, legumes like soybeans contain phytic acid which inhibit the absorption of zinc and iron. Fermentation removes these inhibitors, making the nutritional content easier to access.
In helping gut health, fermented foods can also potentially help improve anxiety and stress, which are often triggered by poor gut health.
Fermentation tips
De Thample says that fermentation is relatively simple, safe and not too pedagogical. With a lactic acid ferment like sauerkraut and kimchi for instance, salt is the only additional requirement aside from the vegetables themselves.
When making sauerkraut, you should massage the cabbage to release the brine. — ABIRAMI DURAI/The Star
Home cooks can also add additional spices or flavouring agents and play around with different fruit and vegetable compositions – based on what they have in their larders or even what their own favourite ingredients are.
“People were fermenting before they even knew what the bacteria were called. So you can use scales and measure everything but really, you can be really laidback about it, because it’s a really safe way of fermenting food.
“When you’re fermenting vegetables in particular, it’s one of the safest ways of preserving it. It’s basically salt (about 2% per weight of vegetable) and vegetables packed into a jar and you’re not going to have anything like botulism hiding around, because using salt will keep it really safe.
Fermentation typically takes one or two weeks but once fermented, these foods can last up to a year. — ABIRAMI DURAI/The Star
“It’s also very cheap to do – salt is really easy to get and it’s cheap. And you can buy really simple vegetables or take anything from your veg drawer.
“So usually when I go on holiday, I pull my veg drawer out and I ferment what I’ve got but anyone can go into their own kitchen and apply this principle and then think about how they want to use them so you know if they’re making a particular curry or you know a particular dish then you could adapt the ferment to complement it,” says de Thample.
De Thample does say though that to ensure ferments are air-tight, it is important to seal jars with a lid as tightly as possible. Most fermented foods are left to ferment for a few days or weeks and can last for up to a year, although taste-testing is still crucial. If it looks or smells off, it is probably off.
