• Fermented foods - like Holly's red kraut - can be used as garnishes, salsas and sides. (Murdoch Books / Ben Dearnley)Source: Murdoch Books / Ben Dearnley
Fermented foods are enjoying a resurgence - Holly Davis explains why that's a good thing for us all.
Holly Davis

6 Oct 2017 - 11:29 AM  UPDATED 4 Dec 2017 - 5:55 PM

One mouthful is all it takes to get hooked on the satisfying textures and dynamic flavours of fermented food and drink – be it a slice of fabulous sourdough bread, raw milk cheese, pickled vegetables, preserved fruit or a bubbling brew whose useful life was extended by these processes. Fermentation is an ever-present force of nature and with just a little understanding, beneficial microbes can be employed to predigest and transform all manner of ingredients into vital additions to our diet. While you care for, crunch and sip ferments with relish, they also offer invisible probiotic support shown to enhance your digestion, immunity, brain function, nutrient levels and more. 

Sharing delectable food is the surest way I know to positively influence a person’s relationship to eating and enthuse them to make their own. On a stinking hot day, a proffered glass of sparkling water kefir often elicits curiosity: ‘This is so refreshing, how did you make it?’, then: ‘May I have some of the culture?’ ‘Definitely!’ is always my answer because this gifting of starter cultures is the way many of these miraculous ferments have travelled the globe to us. Deliciousness is their currency and we their generous means of transport.

One look around my house confirms that an omnivorous wholefood enthusiast lives there. I use time and some of nature’s ubiquitous gifts to facilitate fermentation: her cool earth to maintain a steady temperature while a crock of kimchi ferments, her warm breezes and sunshine to dehydrate umeboshi plums and root vegetables … all of which happens as her ever-present supply of invisible, preservationist microbes do their work. 

Holly Davis shares how to make fermented dishes, such as the Ethiopian flatbread, injera in her new book. 


Things at my house go pop, crackle and fizz in their crocks, pots and jars, or quietly double in size through the night. Some residents announce their presence, first by their promising scent, others with what some would term ‘a potent pong’.

Most ferments are surprisingly easy to make and the active doing doesn’t take long. If you are new to this, I suggest you pick one ferment and give that your full attention until you have developed a rhythm for its care. Once it has become a part of your life, keep experimenting until you find those that make your heart and stomach sing. 

A taste for sour

The ferments in my new book Ferment cover the broadest range of tastes, from very sweet (the rice drink amazake) to earthy (tempeh) and salty (miso pickles). But the most common flavour of fermentation is sour, in varying degrees. This sourness is caused by a massive group of beneficial lactic acid-producing bacteria called lactobacilli. Why does a salted raw cabbage turn to sauerkraut (sour cabbage)? Because beasties invisible to the naked eye, including a plethora of lactobacilli bacteria, cling to every leaf of that cabbage. These come from the soil, air and anyone who touches the cabbage. When that cabbage is cut, salted and squashed into a jar that is then sealed tightly, the salt-and-acid-tolerant beasties get busy multiplying by converting the sugars (starches) in the cabbage into various acids, carbon dioxide (bubbles) and ethanol (alcohol), boosting the cabbage’s nutrient profile as they go. Sourness increases as more acids are created with time. The types of beasties in the jar also transform, and so it is that the sourest ferments contain the most acid-tolerant strains of bacteria.

Your role as ‘fermenter’ is to facilitate this seemingly magic process by creating the most favourable conditions possible for the micro-organisms you wish to employ to preserve and enhance your chosen foodstuffs, while guarding against infiltration by putrefying bacteria, which would otherwise cause the food to spoil.

Since fermented foods are shown to do their most valuable work beyond our highly acidic stomach, eating small amounts of quite sour ferments on a regular basis may be useful.

Why ferment?

When food is fermented, it is predigested by the micro-organisms present. The texture and flavour transform and nutrients that might otherwise have been unavailable to us are made useful. And where possible, fermentation can detoxify the ingredients being fermented. Many of the foods we might choose to ferment contain various anti-nutrient compounds, making them hard to digest and their minerals difficult to extract. We can utilise fermentation to address specific toxic compounds found in many foods (though this does not refer to all toxic compounds). The anti-nutrients found in grains, legumes, nuts and seeds are covered in more detail in chapter one of my book.

The process of fermentation preserves ingredients, making them safe to eat for weeks, months or in some cases years beyond their fresh state. This is a massive benefit if you live without refrigeration, but in this day and age why bother to ferment foods? Variety, complex flavours and textures or to preserve an excess of seasonal produce may all be reason enough, but there are other benefits, which might encourage you to join the fast-growing band of fermentation revivalists.

Used ferments such as Holly's brined beetroot  to up the ante on health and flavor with a meal


Current studies demonstrate that the genes of our resident microbial communities have the power to influence our weight regulation, immune system, respiratory system, digestion and the absorption of nutrients in the foods we eat. Beneficial gut bacteria help us in the production of vitamins B3, B5, B6, B7 (biotin), B9 (folate), B12 and K, which enhance absorption of minerals, fight off pathogens, digest food, metabolise drugs and influence metabolism.

Gut bacteria also have a massive role to play when it comes to our mental well-being and the workings of our nervous system. A modern lifestyle with high stress levels, highly processed and sugary foods and drinks, along with the overuse of antibiotic medicines, cleaning and beauty products loaded with synthetic ingredients can all damage our inner ecology. More and more people are suffering from a myriad of auto-immune diseases, heart disease, type-2 diabetes, obesity, allergies, dermatitis, dysfunctional breathing, mental health issues, cancer, irritable bowel syndrome, autism and more. We now recognise that by altering and damaging our inner ecology, we suffer ever more of these ills.

Current research tells us that it is time to take better care of our co-inhabitants. Eating properly fermented live foods and drinks, as part of a diverse, fibre-rich wholefood diet, is one way to support the thousands of species we share our human home with and provide them with what they need to do their best work. Consuming whole grains, legumes, nuts and seeds that have been properly prepared is an excellent starting point.

When food and drink are able to supply a diverse range of probiotics, employing expensive lab-produced strains to attempt the same job is often unnecessary.

Fermentation revival

Had we all been born 80 or more years ago, the knowledge of how to ferment foods would have been transferred to us. We would have witnessed or assisted in the traditional processes and techniques employed by our ancestors to preserve the harvest, wherever in the world we may have hailed from.

All over the world our ancestors put these invisible beneficial micro-organisms to work, with no scientific terminology to explain what was at play. However, there is much evidence that they recognised the potency and benefits of regular inclusion of these foods in their diet.

Fermented foods are so integral to communities that when people depart from their homelands, their starter cultures are vital travelling companions. In this way, displaced people are able to somewhat maintain their food culture. After all, food is a vital part of our cultural identity.

Fermented foods speak to us of the legacy of our forefathers and current research is shining a light on how vital a role these foods play in the restoration and maintenance of good health.

This is an edited extract from Ferment by Holly Davis (Murdoch Books, hb, $45).  You can visit Holly's website here and find her on Instagram here or Facebook here

Cook the Book

Red cabbage, arame and ginger kraut

Give the traditional sauerkraut a kick in both the flavour and colour department with this version that pairs beautifully with rich foods.

Fermented foods - like Holly's red kraut - can be used as garnishes, salsas and sides.

Black turtle beans with smoky chipotle creamed corn

These two elements pair deliciously together, but also stand tall on their own. Serve up with other fresh ingredients like coriander - perfect when entertaining. 

Turtle beans with chipotle creamed corn

Millet idli or dosa

This Indian fermented batter can be used to make either steamed cakes (idli), or crispy pancakes (dosa)

Indian dosa

Brined beetroot with orange and ginger

The brined beetroot can be diced and used to top soups or casseroles and is perfect served with a cheese platter.

Brined beetroot


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