Foods to Boost Your Immune System


As I write this column Covid 19 numbers are escalating in leaps and bounds. We’re back in strictest Level 5 lockdown and virtually everyone’s life is on hold. We have postponed the start of our Spring 12 Week Course. Students who have been looking forward to joining us are biting their nails wondering when they will be able to start the course they have so looked forward to, in some cases for several years. C’est la vie at present….

Little Christmas has come and gone….this year the women of Ireland could not get together to celebrate but those of us who are fortunate to be still well can concentrate on counting our blessings and focus on boosting our gut biome, mental health and immune systems with nourishing, wholesome food.

Many factors affect our immune system, our lifestyle, sleep habits, stress levels, environment, genes….

We can’t do anything about our genes, we are what we became at the moment of our conception. Exercise helps, adequate sleep does too, we all know how much easier it is to pick up a cold or flu when we are exhausted after a long period of stressful work.

But like any army our immune system marches on it’s stomach, scientists acknowledge that those who live in poverty and are malnourished are more likely to succumb to infectious diseases. Despite that there are still relatively few studies on the effect of nutrition on the immune system of humans.

You don’t have to be a doctor or nutritionist to know that the type of food we eat impacts on our wellbeing.  Covid 19, particularly this mutant strain is unquestionably highly contagious. One certainly can’t say for sure that lots of nutritious food will protect us but it can’t hurt to eat delicious vitamin and mineral rich food. Vitamin A and D are known to support our immune systems and work together like twins. Vitamin D comes from sunlight, so dash out and lap up as much winter sun as you can – it’s much more effective than taking Vitamin D pills.

Vitamin A comes principally from liver and pure fermented cod liver oil but also egg yolks and unpasteurised dairy products. Each and every one of the vitamins, minerals and trace elements are crucial in their own particular way.

I’m a big believer in the power and the nourishment of broth. Any bone broth really but particularly chicken broth so soothing and restorative. It’s super easy to make particularly if you have a slow cooker.

Making bone broth is a way of working, instead of chucking things out, collect all the vegetable peelings, herb stalks poultry carcasses, bones and giblets in a ‘stock box’ in your freezer. When it’s full to the brim, make a celebration pot of stock. Then strain and degrease if necessary, cool and refrigerate or freeze to enjoy the next time you feel like a pick-me-up.

Broth is concentrated stock, the French word for stock is Fond which means foundation in English. Chicken broth is probably the most useful but fantastic broth but can also be made from beef, lamb and game bones.

A turkey carcass also makes a delicious stock but no doubt that’s long gone now so if you didn’t use it this time make a mental note to make fine big pot of broth next time round. It’s well worth reminding ourselves that back as far as the mid 400’s BC, Greek Physician Hippocrates (who apparently lived to the ripe old age of 90) stated “let food be thy medicine and medicine be thy food”.

At the APC (Alementary Pharambotic Centre) microbiome Institute at UCC Professor Cryan & Professor Dinan and their team have been investigating the link between gut health and mental health for almost a decade now, with fascinating results.

Not surprisingly, heavily processed foods, sweeteners and emulsifiers have a negative effect on the biodiversity of our gut biome. It may sound boring and passé but all we need is real living food, lots of fibre and green vegetables and if you fancy some green tea and dark chocolate. Fermented foods are super important also so seek out natural sourdough bread (beware there’s a lot of faux sourdough around), sauerkraut, kimchi, water and milk kefir, better still make it yourself. Here are some easy recipes to get you started, virtually nothing you buy will be as good and I guarantee you’ll feel the better of it.

Chicken Stock

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 (if you can get chicken feet, they will add lots of collagen and flavour). Then you can make a really good-sized pot of stock and get 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

4 outside celery stalks or 2 lovage leaves

2 carrot, cut into chunks

a few parsley stalks

sprig of thyme

6 black 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/17 1/2 cups) cold water. Bring to the boil. Skim the fat off the top with a tablespoon. Simmer very gently for 3–4 hours. Taste, strain and remove any remaining fat. Do not add salt.


For a more intense flavour, boil down the liquid in an open pan until it reduces to about half of the original volume. Taste and add salt.


Pheasant or guinea fowl stock is also made on the same principle as chicken stock. Use appropriately in game dishes.


Goose or duck stock may be made in the same manner as chicken stock. However, some chefs like to brown the carcasses first for a richer flavour and darker stock. Use for goose and duck recipes such as Duck, Ginger and Noodle Broth

Duck, Ginger and Noodle Broth

Serves 6 – 8

350-450g (12 – 16ozs) cooked duck meat, shredded

1.8 litres (3 pints) duck stock

2 1/2 inch (6cm) piece ginger, thinly sliced

3 star anise

4-6 spring onions, roughly chopped

1 teaspoon black peppercorns

100g (3 1/2 ozs) rice noodles

2 tablespoons nam pla (fish sauce)

4ozs (110g) Chinese cabbage, thinly sliced or 8ozs (225g) sprouting broccoli

6 tablespoons fresh coriander leaves

OR Thai basil leaves

2 red chillies, thinly sliced

crispy shallots

Bring the duck stock slowly to the boil with the ginger, star anise, spring onions and peppercorns.  Simmer gently for 30 minutes.  Strain the broth.  Add the fish sauce to the strained broth.

Pour the boiling water over the noodles. Bring the stock to the boil, add the cabbage or broccoli and simmer for 3 or 4 minutes.  Strain the noodles.  Divide them between the serving bowls, top with the duck pieces.  Taste and correct seasoning of the broth.  Ladle the broth and cabbage or broccoli over the noodles and duck.  Top with coriander leaves or Thai basil leaves.  Scatter with thinly sliced chilli and crispy shallots if you can find them.

Serve as soon as possible.


Thank you @pennyportous for these delicious kimchi and sauerkraut recipes from The Fermentation HQ at Ballymaloe Cookery School.

Makes 2 litres approx.

1kg (2 1/4lbs) Chinese cabbage, roughly chopped

1 carrot, chopped

12 spring onions

8 garlic cloves

5 chillies

6 tablespoons ginger

1 tablespoon fish sauce

2 Litre Kilner Jar

Make a brine of 2 litres of water with 8 tablespoon sea salt.  Cover the cabbage and carrots with the brine in a big bowl and put a weight on top to keep them submerged.  Leave overnight or for a few hours at least.

Put the spring onions, garlic, chillies, ginger and fish sauce into a food processer and chop finely. 

Drain the cabbage, keeping some of the bring solution. 

Mix the onion paste into the cabbage.  Stuff tightly into a 2 litre (3 1/2 pints) Kilner jar.  Use a small jar to weigh everything down the mixture.  Top up with small bit of brine to keep submerged. 

Ballymaloe Sauerkraut

At its basic sauerkraut is chopped or shredded cabbage that is salted and fermented in its own juice.  It 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.  Try to use organic vegetables if available.

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

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 counter top 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.

Penny Allen’s Water Kefir

Water kefir is a superfast fermented drink made using a starter culture or “grains”. These grains are essentially a SCOBY (Symbiotic Colony of Bacteria and Yeast). These cultures convert sugar water into a probiotic, enzyme-rich refreshing drink filled with friendly microorganisms that can help bring balance to your microbiome. It’s very easy to make at home and at its most basic it’s just fermented sugar and water, ready to drink in just a couple of days!

120g (scant 4 1/2oz) water kefir grains 

70g (scant 3oz) organic sugar – the less sugar you add the quicker it will take to ferment

2 organic apricots or equivalent of other dried fruit – such as figs, dates, prunes, raisins

1 litre (1 3/4 pints) of water – filtered or dechlorinated  

slice of organic unwaxed lemon or lime

1 x 1 1/2 litre (2 1/2 pints) Kilner jar 

Making Water Kefir for the first time

Put the sugar into the 1.5 litre Kilner jar. Pour in the filtered or dechlorinated water and stir well with a wooden spoon until the sugar has dissolved into the water. 

Now strain your starter jar of water kefir, catching the grains in a sieve and discard the liquid they have been in. 

Tip these grains into the sugar water in the Kilner jar. Add the dried fruit and slice of lemon and secure the lid.

Leave out on a countertop to ferment at room temperature for 2-4 days. After day 2 start to taste the kefir to see if it’s to your liking – you decide when it’s ready – the longer it ferments, the less sweet it will be, the sugar being converted into beneficial organic acids.

When the kefir acquires the flavour that suits you, lift out the dried fruit and lemon (which should be floating on the surface). Strain the liquid through a sieve, catching the kefir grains in the sieve. Pour the liquid into a bottle – secure with a lid and store in the fridge – it will carbonate nicely in the fridge – just be careful when opening! The kefir can be enjoyed as is or you might choose to flavour it – we call this the second fermentation – see below.

Now make your next batch.

Water kefir wants to be made over and over again. You have your grains in a sieve so just put more sugar into the 1.5 litre Kilner jar and add 1 litre (1 3/4 pints) of filtered/dechlorinated water. Stir once again until the sugar has dissolved into the water and add grains to jar. Add a new slice of lemon and 2 pieces of dried fruit. Secure the lid and leave to ferment once again on the countertop for 2-4 days, tasting each day until it’s to your liking.

Grains might gradually multiply over time. You can divide them and give some away or you can make larger quantities of water kefir in larger jar. 

If you want to take a break from making water kefir you can feed the grains extra sugar- perhaps double the amount you usually add and then it can be left on the counter for a week – maybe two. Some people put the jar into the fridge to really slow down fermentation but I would suggest that a week in the fridge is the most you should do cos the grains will become too dormant and difficult to revive.

Second Fermentation

After transferring your water kefir into a bottle add a handful of one of the following to your taste.

fresh or frozen raspberries/blackberries

fresh or frozen strawberries

mango, pineapple and lime 

3-4 small pieces of Crystallised Ginger sliced thinly

several crushed mint leaves and juice of 1 lemon

splash of rosewater and some crushed cardamom seeds

1/2 tablespoon elderberries, 1 tablespoon rosehips and zest from 1 orange

1 vanilla pod (which can be reused many times)

Milk Kefir – Penny Allen

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

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 a vanilla pod and honey 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.

Coconut Milk Kefir

Use 2 tablespoons of milk kefir grains and replace the milk with 1 can of coconut milk and proceed as in master recipe. 
Note: The original grains need to be feed with milk every week or every three or four batches as they need lactose to keep active.  The lactose is digested by the kefir so it’s still suitable for those intolerant to lactose. 

About the author

Darina Allen
By Darina Allen


Past Letters

  • Recipes