World Microbiome Day


Celebrate World Microbiome Day on June 27th.
In our crazy world, many of us know far more about the lives of celebrities than we do about the source of the food we and our families eat.  Nonetheless, we have become increasingly paranoid, can’t eat this, can’t eat that…meanwhile in supermarkets, free-from and supplement aisles are gaining more space…

For the past year and a half, we’ve lived in a climate of fear. Covid-19 has made us even more paranoid about bacteria, microbes, viruses….
We sanitize from morning until night, carry little phials in our handbags and worry endlessly that there are bacteria waiting to pounce everywhere we go…Scientists and microbiologists are becoming ever more concerned. In our sanitizing frenzy, we have also eliminated many beneficial bacteria that help to protect us. Consequently, the pathogenic bacteria are becoming stronger and stronger because nature always triumphs in the end

Humans have co-evolved with microbes, bacteria, virus, fungi, archaea…since time began.  They are everywhere, on plants and animals, in water, soil, food and all over us humans.  Most are beneficial, a few are pathogenic.  They are also in the soils and oceans of the world, on every surface, there are trillions on the human body, on our skins in our mouths and 90-95% reside in our gut microbiome.   In Ayurvedic and Chinese healing traditions, the dialogue between the gut and the brain has long been recognised, however Western medicine failed until relatively recently to appreciate the complexity of how the brain, gut and microbiome communicate with each other.

Scientific study of the gut microbiome is relatively new.  A growing body of research worldwide, with much done in UCC in Cork, has proved beyond any doubt that the biodiversity of our gut microbiome, has a profound impact not just our physical but also on our mental health.

The invisible world of microbes is a fascinating one, filled with untapped potential, microbiologists say that much has still to be understood. 

But here’s a taste of what they’ve discovered so far:  

  • Marine microbes produce most of the oxygen we breathe and can absorb as much carbon dioxide as plants do on land.
  • Microbes in the soil fix nitrogen – changing it from a gas in the atmosphere to a form in the soil that plants can use to grow.
  • Some microbes even have the capacity to break down methane gas, helping to slow climate change.
  • In our homes, composting microbes help us recycle our green waste (plants, vegetables, fruits) and recover nutrients to enrich the soil in our gardens.
  • Up to a third of the food we consume is produced by microbes. We can use microbes to extend the shelf-life of our foods and prevent food waste by fermenting foods at home.
  • At a larger scale, microbes can contribute to the circular economy by converting waste (e.g. food production waste) into fuel and thus provide new and sustainable opportunities for the food and feed production.

But in this article, I will concentrate on how to boost our personal gut microbiome.  World Microbiome Day 2021 focuses on the potential of microbiomes for a sustainable future.  It’s all about biodiversity, the greater the variety of fresh organic food we eat, the more healthy and diverse our gut microbiome becomes.  Once again, it’s not rocket science, gut microbes love real food.  They are totally confused by fake food so let’s cut ultra-processed food totally from your diet and concentrate on sourcing as much seasonal produce as possible with lots of fresh vegetables for roughage.  Nature provides what we need year-round.  Let’s learn how to recognise beneficial and edible food in the wild, incorporate them into our diets.  They carry the antibodies of our area and have maximum nutrients because unlike many other foods they have not been manipulated to produce maximum yield at minimum cost, which is sadly the primary focus in mass food production these days to the detriment of our overall health.  

Biodiversity is the key, eat as wide a range of seasonal and chemical free range of foods as possible.  So, concentrate on boosting your gut-biome.  Local honey, local pastured eggs from organic free-range hens, local organic meat from free-ranging grass fed animals and organic raw milk also boost our microbiome. Fermented foods are another must have, sauerkraut, kimchi, kombucha, water and milk kefir. Try to make your own, they’ll be infinity more complex than most of what you can buy.  Thick unctuous yogurt preferably made from organic milk and collagen rich home-made home broths.  In fact, all real food will stimulate and delight the almost 2kg of microbes in our gut and you’ll feel the better for it both mentally and physically. Keep washing your hands but be careful of over sanitizing, you may well be doing more harm than good.

For World Microbiome Day on June 27th, APC Microbiome Ireland SFI Research Centre is hosting Microbiome Friendly Brunch Demonstration – Darina Allen in conversation with John Leech, an APC Microbiome Ireland SFI Research Centre, PhD student based in Teagasc Food Research and research officer with MASTER.

This very special online cookery demonstration will cover the following dishes – Water Kefir and Milk Kefir, Yoghurt- Labneh, Honey, Almonds, Porridge, Shakshuka with Sourdough, Granola and Pan Grilled Mackerel Miso. The cookery demonstration will commence at 11am on World Microbiome Day and be available on demand thereafter.

Darina and John will discuss how the various ingredients benefit the microbiome as the cookery demonstration progresses. They will also discuss sustainability – the theme for World Microbiome Day 2021 – and a cause which is high on the agenda for Darina Allen and Ballymaloe Cookery School.

Visit for more information, a recipe booklet and a link to book your free tickets via Eventbrite

Ballymaloe Cookery School Homemade Yoghurt

It’s really easy to make your own yoghurt, the end result will depend on the quality of the milk.  We make our natural yoghurt from the rich milk of our small Jersey herd.  First it is boiled, pasteurized and then allowed to cool to lukewarm.  This destroys any unwanted bacteria in the milk which could interfere with the bacterial action of the yoghurt bacillus.

600ml (1 pint) fresh milk

2-3 teaspoons live yoghurt or natural bacillus

Heat the milk to 90°C (194°F) in a heavy bottomed saucepan.  Allow to cool to 42°C (107.6°F).  Gently stir or whisk in the yogurt. Leave in the saucepan or pour into a deep terracotta bowl or a wide mouth flask works brilliantly.  Cover and put into a warm draught-free place until set.  This usually takes about 14 hours.  The cooler the temperature, the longer the yogurt will take to set, but too high a temperature will kill the bacillus and the yogurt will not form (over 50°C/122°F).

The simple aim is to provide steady even warmth to allow the bacillus to grow.  Remember to keep back 2 tablespoons of yoghurt as the starter of the next lot.

Yoghurt with Honey, Dates and Almonds

unsweetened natural yoghurt, very cold

runny honey

Medjool dates

thick cream

almonds (with the inner brown skin left on i.e unblanched)

  1. For each person half-fill a pudding bowl or glass with yoghurt.
  2. Stone dates and chop them roughly.  Put a few on the top of each helping of yogurt.
  3. Spoon a good dollop of thick cream over the top, then trickle over 1 teaspoon of runny honey.
  4. Scatter a few more coarsely chopped almonds on top.  Pistachio nuts are also delicious and perhaps a few shredded mint leaves.

Penny Allen’s Milk and Honey Kefir

Milk kefir is a probiotic drink a bit like a slightly effervescent yoghurt.

It is made with kefir grains and milk. The grains can be used again and again and will multiply if well looked after. The grains are not related to cereal grains and neither are they related to water kefir grains. The grains are a bio-matrix made by yeasts and bacteria. There are many ways to enjoy kefir. It can be added to smoothies, used as you would buttermilk, great as a marinade to tenderise meat or add spices to make lassi.

Basic Recipe

1 tablespoon milk kefir grains

250ml (9fl oz) milk

honey to taste, vanilla or spices

Put your grains into a glass jar.

Add the milk and stir gently with a non-metal spoon.

Cover the jar with a clean cloth and put somewhere out of direct sunlight.

Let it sit for 12-24 hours until it reaches the desired sourness.  Stir from time to time. This helps it to ferment evenly. Taste it after 12 hours.

When the kefir has reached the desirable taste, strain the kefir through a plastic sieve into a bowl. You might need to help it through with a plastic spoon. You will be left with the kefir grains in the sieve, ready to be reused. Don’t be tempted to wash them.

You can now make the basic recipe again. As the grains multiply you can make larger batches.

To the strained kefir you can now add something like honey, a vanilla pod or spices to add flavour.

If you want to take a break from brewing kefir just put the grains into a fresh cup of milk and put it in the fridge. This will slow down fermentation for a few days.

Penny Allen’s Basic Sauerkraut

At its basic sauerkraut is chopped or shredded cabbage that is salted and fermented in its own juice.  A preservation method that has existed in one form or another for thousands of years and sailors have carried it on ships to ward off scurvy because of its high Vitamin C content. 

800g (1 3/4lb) of cabbage


500g (18oz) of cabbage plus

300g (10oz) of mixture of any of the following: grated carrot, turnip, celeriac, onion

3 level teaspoons sea salt

1 x 1 litre Kilner jar or similar receptacle

1 x small jam jar to act as a weight inside the lid of the 1 litre jar

Wash the cabbage if it’s muddy. Take off any damaged outside leaves. Quarter the cabbage, core it and then finely shred each quarter.

Mix the cabbage and the rest of the ingredients together in a large bowl.  Using your hands, scrunch cabbage and other vegetables with the salt until you begin to feel the juices being released.  Continue for a few minutes. Pack a little at a time you’re your Kilner jar and press down hard using your fist – this packs the kraut tight and helps force more water out of the vegetables.  Fill the Jar about 80% full to leave room for liquid that will come out of the vegetables as it starts to ferment.

Place a clean weight on top of cabbage (a small jar or container filled with water works well).  This weight is to keep the vegetables submerged under the brine. This is the most important thing to get your ferment off to the right start. (Under the brine, all will be fine!)

Sit the jar on a plate just in case some brine escapes while it is fermenting. Place on a countertop and allow to ferment for at least 5 days. Ideally leave it for 10 days to 2 weeks.  As you eat the kraut make sure the remainder is well covered in brine by pushing the vegetables under the brine and sealing well.  It will keep for months, the flavour develops and matures over time. Once you have opened it, it’s best to keep it in the fridge where it will last for months.

Chicken Stock and Broth

This recipe is just a guideline. If you have just one carcass and can’t be bothered to make a small quantity of stock, why not freeze the carcass and save it up until you have six or seven carcasses and giblets, then you can make a really good-sized pot of stock and get the best value for your fuel.

Stock will keep for several days in the refrigerator. If you want to keep it for longer, boil it up again for 5–6 minutes every couple of days; allow it to get cold and refrigerate again. Stock also freezes perfectly. For cheap containers, use large yogurt cartons or plastic milk bottles, then you can cut them away from the frozen stock without a conscience if you need to defrost it in a hurry!

Makes about 3.5 litres (6 pints)

2–3 raw or cooked chicken carcasses or a mixture of both giblets from the chicken (neck, heart, gizzard – save the liver for a different dish)

1 onion, sliced

1 leek, split in two

2 outside celery stalks or 2 lovage leaves

1 carrot, cut into chunks

a few parsley stalks

sprig of thyme

6 peppercorns

Chop up the carcasses as much as possible. Put all the ingredients into a saucepan and cover with about 3.4 litres (7 pints) cold water. Bring to the boil. Skim the fat off the top with a tablespoon. Simmer very gently for 3–4 hours. Strain and remove any remaining fat. Do not add salt.


Continue to cook for a further hour or so.

Add a tablespoon of wine vinegar which helps to extract even more minerals and helps to breakdown the cartilage and other connective tissues in the bones of the chicken, which helps speed up the formation of gelatine in the stock. Store in the fridge for 3-4 days or freeze in convenient containers.

Chicken Broth with Julienne of Vegetables

1.5 litres (2 1/2 pints) of well-flavoured homemade chicken stock


50g (2oz) carrots

50g (2oz) celery

50g (2oz) white turnip

50g (2oz) leeks

flat parsley

4 spring onions, cut at an angle

First, julienne the vegetables.

Peel and cut the carrot, celery, turnip and leek into very thin strips

Heat the broth, season with salt and freshly ground black pepper.  Add the julienne, bring back to the boil and simmer gently until the vegetables are just cooked, 5-6 minutes. 

Ladle into bowls and scatter with parsley and spring onion.

About the author

Darina Allen
By Darina Allen


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