Traditionally prepared oats (fermented porridge)

If you want to have a porridge that is made from traditionally prepared oats then this is your guide! They are so simple to make and make the perfect cosy start to the day. Best served with lots of butter, cream or your preferred whole food fats.

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After putting off writing this post for years- here it finally is! A quick guide on how (and why) to prepare oats by fermenting/souring them first. 

Let’s jump right in?

Traditionally prepared oatsWhat does ‘traditionally prepared oats’ mean?

Preparing your grains traditionally is similar to brushing your teeth- you don’t have to do it, but its better if you do. 

Only until recent years humans all across the globe went to great lengths to prepare foods like grains, legumes, nuts and seeds in a very specific way. The process may have changed between cultures, regions and religions but was a (basically) a unanimous approach to preparing food.

The process was time consuming and involved a lot of hard work- depending on the food this would include washing, soaking, sprouting, fermenting, hand milling, polishing, cooking, adding companion spices and various other techniques. The process was meticulously carried out to turn the food from one that was inert into a living food, full of bioavailable nutrients that were nourishing and free from digestive irritants. 

Oats, for example, were traditionally left in the fields to sprout before being collected (potentially then rolled, or not) and fermented in the home for 4-5 days before being cooked. The process was a nourishing tradition that served as a main food source for the Scotts, and for the rest of the world is a process that seems to have been almost lost and transformed into a fast-food tradition that does not have the same health benefits. 

To understand why we want to eat traditionally prepared oats we need to understand anti-nutrients and the enzyme phytase

Traditionally prepared oats (fermented porridge)Understanding anti-nutrients

Like all living things, grains, nuts, seeds and legumes are pretty clever. They have a mission- to continue on the life cycle for their species, and they have some pretty sneaky ways of doing so.

A living plant produces a grain (nut, seed ect) which then drops to the ground to lay dormant for some months. A few seasons later this grain will sprout new life to create the next cycle of life, but, the grain has to first survive those months of laying dormant on the ground.  

The dormant grain creates certain compounds (that we commonly refer to as anti-nutrients, like phytic acid) to protect itself during this time. Phytic acid locks away phosphorus, a vital nutrient for plant growth. Phytic acid also binds to minerals in the gut, preventing absorption of this nutrients form the food, and have also shown to inhibit key enzymes in the gut like pepsin, amylase and trypsin. When we inhibit enzyme activity, we inhibit digestive function. 

So, in a nut shell- if we eat a lot of grains, nuts, seed and legumes we should aim t prepare these traditionally as often as possible to maximise nutrient absorption and our digestive health. 

Understanding phytase

Phytase is an enzyme present in many foods, and has an important roll in deactivating phytic acid. When some grains, for example, is added to  a warm, acidic water source (like Spring rain water) the naturally present phytase enzyme breaks down the phytic acid to stimulate the production of new life.

Indeed, when we soak some grains in warm, acidic water we mimic this process and the phytase enzyme is activated, breaking down and removing the  phytic acid. 

The issue with oats, however is they are a low-phytase grain. This means that soaking oats in warm, acidic water will do very little to reduce phytic acid

Low vs high phytase grains are;

  • Grains low is phytaste include; oats, brown rice, corn, millet. Soaking these grains will not reduce anti nutrients. 
  • Grains naturally high in phytase include; rye, wheat, spelt, barely, buckwheat. Soaking these grains will reduce anti-nutrients. 


All you really need to know that some grains simply require lukewarm, acidic water to remove anti-nutrients. these are wheat, rye, barely and buckwheat. Some other grains require more than soaking in lukewarm, acidic water to remove anti-nutrients. These include oats, corn, millet and brown rice. 

Traditionally prepared oats

Methods of traditionally prepared oats 

First, let me say none of these methods are specifically meant to represent traditional preparation by any specific culture or region. They are simple ways you can prepare your oats at home to mimic traditional methods. 

What is lukewarm, acidic water?

Nuts, seeds, grains and legumes prefer an acidic medium (acidic water) because this helps to wake up or activate the enzyme is the food. Room temperature water is fine, but if your local weather is very cold its best to try and add water around 20 C and keep it in a warm place.

To create an acidic medium, we can add the following things;

  • Lemon juice
  • Apple cider vinegar (or any vinegar
  • Salt
  • Active (natural or homemade) yoghurt
  • Whey

Soaking your oats

If fermenting your oats sounds like too much for you right now, start here. 

  • Step one is to soak your oats overnight in an acidic medium (see above). If you do not plan to ferment your oats you can do this precess in a bowl. If you plan to ferment your oats then soak the oats in a fermenting crock or large vessel with an airtight lid. 
  • Step 2 is to add some of the enzyme phytase if possible. Freshly flour of wheat, rye or buckwheat (if gluten free) will do this. Sourdough discard would also work well. 
  • In the morning you can either cook your oats or have a go at fermenting them

Traditionally prepared oats (fermented porridge)Fermenting your oats

Fermenting your oats is a natural continuation of the above steps- however we need to be a bit more specific about what we add, and heat we ferment in. 

  • To ferment oats you should first find a large vessel that is suitable for fermenting. It should be glass or ceramic and ideally have an airtight lid. If you don’t have a jar with an airtight lid that’s ok, you just need to watch the ferment more closely. Make sure the jar/crock is very clean
  • Add oats to the jar/crock and cover with water about 2cm above the oats. The oats and water should be at least 5cm below the rim line. 
  • Add a starter culture to help with fermenting. This can be any active culture, including; homemade (or active, unpasteurised) milk kefir, water kefir or yoghurt, active apple cider vinegar (with the mother), sourdough starter, whey, homemade kombucha. Note- both vinegar and kombucha do leave some of their flavour in the oats, so I don’t like these. 
  • Add some of the enzyme phytase to the mixture if you can (see tsp 2 in soaking your oats)- note, there is no need to do this if you added sourdough starter/discard as your starter culture. 
  • Secure the lid and leave in a dark but warm area to ferment for 1-5 days. 

Fermented oat porridge

Traditionally prepared oats (fermented porridge)Cooking your oats

  • After fermenting to you liking you can now cook the oats. Add to a pot with water/milk and bring to a gentle simmer, cooking for around 10 minutes. Stir throughout or as regularly as possible. 

That’s it! A little bit different to the instant-oats culture we have here (in Australia, anyway) isn’t it? 

Traditionally prepared oats (fermented porridge)

Traditionally prepared oatsFrequently asked questions

Does fermenting make the oats gluten free?

No- fermenting will do nothing to the gluten in your oats. It will, however, make them easier to digest but if you are gluten free you must source certified gluten free oats like these ones here

Im scared about poisoning my family- help!

I get this question A LOT, especially in my Instagram messages. I get it- we have lost the art and know how of fermenting, and it can seem scary.

First and foremost it is import to understand that fermenting is a traditional way to STORE FOOD SAFELY. It has many other benefits, but primarily it was about food preservation and by its very nature it helps us to store food safely. If you learn the basic principles to follow, and keep an eye/nose out for mould/disgusting smells, everything will be ok.

Knowledge is power. First off, have a quick read of my blog here on simple rules when fermenting and if you want to dive deeper I recommend this book here

Investing in a fermenting jar like this one has been huge for me, as the airtight seal ensures environmental bacteria and yeast cannot get into my ferment. 

Finally- always remember to trust your senses. If you can see mould, throw it. It the ferment smells foul, Thrown it. If it feels limy- throw it. 

The best way to loose the fear is to start fermenting straight away. 

I hope you enjoy this recipe for Traditionally prepared oats (fermented porridge) as it offers you some food for thought. I love the practice of traditional preparation, as it allows me to slow down and remove myself from our fast paced culture, if only for a little while 🙂

After more fermenting recipes? Try;

We welcome your feedback and reviews! If you have any questions or reviews, please leave them below. We love hearing from you.


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Traditionally prepared oats

Traditionally prepared oats (fermented porridge)

5 Stars 4 Stars 3 Stars 2 Stars 1 Star 4.8 from 5 reviews
  • Author: Jade Woodd
  • Prep Time: 1-5 days
  • Cook Time: 10 mins
  • Total Time: 0 hours
  • Yield: 3-6 serves 1x
  • Category: Breakfast
  • Method: Fermenting
  • Cuisine: Scottish-inspired


If you want to have a porridge that is made from traditionally prepared oats then this is your guide! They are so simple to make and make the perfect cosy start to the day. Best served with lots of butter, cream or your preferred whole food fats. This recipe is inspired by nourishing traditions but is not meant to represent traditional preparation form any specific people’s or regions. 



3 cups rolled oats, certified organic if needed

3 1/2 cups filtered water

Optional- 1 tbsp fresh rye, wheat or buckwheat (if gluten free) flour

Your choice of 1 of the following starters;

1/2 cup unpasteurised coconut water kefir, or;

1/2 cup homemade yoghurt, unpasteurised natural yoghurt, whey or milk kefir (see notes), or:

1/4 cup homemade sourdough discard

To cook

Pinch salt

Milk or water

To serve (per bowl)

1 Tbsp butter or cream

Yoghurt of choice

Drizzle of honey


  1. Add oats to a fermenting crock or large glass jar. I use a 3L Kilner crock, but you could use anything that is glass or ceramic, ideally with an airtight lid (or second best, a tightly fitting lid). Ensure this vessel is very clean- you do not need to sterilise it, but wash in very hot water and allow to air dry. Avoid using cloths or tea towels on the inside of the jar as this can transfer bacteria.
  2. Add oats to the jar followed by the water, optional flour and your choice of starter. For more ideas on what starter culture you can use read the blog post above. Give this a little stir, then secure the lid.
  3. Place your jar in a dark but warm place for 1-5 days. This should be out of direct sunlight, and somewhere you won’t forget about. In the winter months I turn on the light in my oven and place all my ferments in there- it creates the perfect temperature. Note- there is NO right amount of time to ferment. The speed to which your oats will ferment will depend on how active your starter was AND the temperature. In summer months 24hrs might be enough, in the middle of winter it can take up to a week. It is ready when it smells slightly sour. This will become easy with practice- you will notice how strongly you like your oats to be fermented only by practicing it and tasting them- sorry were are no short cuts here! As a first time rule, they are fermented enough when they smell slightly sour.
  4. FOOD SAFETY. Fermenting is a natural process and something that is very easy to do safely once you know what to look out for. First and foremost you should trust your nose- the oats should smell pleasant- if your oats ever smell foul something has gone wrong and you should discard them. Likewise if you see mould of any sort discard the batch and start again. ALWAYS add the starter culture as advised above (this protects again harmful bacteria), and finally read this post here for more info on good house keeping while fermenting.
  5. Once you have fermented your oats to your liking you can now transfer the mix to the fridge, and cook batches as desired- see next step. It is up to you whether you want to strain the liquid off of the oats after fermenting or not. Either is fine.
  6. Add 1/2cup of the fermented oat mixture to a small cooking pot with 1/2 cup of water or milk, and a pinch of salt. Adjust ratios as needed- if you’re after a larger meal then 1 cups fermented oats to 1 cup milk/water. Bring to a gentle simmer, and cook away for 10 minutes on low heat. Traditionally oats would be stirred or beaten the whole time- this makes for THE creamiest oats and is recommend (but is a bit of an arm workout).
  7. Pour hot, creamy oats into a bowl and top with your choice of butter or cream, yoghurt and a drizzle of honey. Add any extra delights you like!


  • I’ve never made this with store bought yoghurt, but look for a Greek style yoghurt that is organic, pot set and contains only milk and bacteria strains.
  1. Hi ! Thanks for that, im a cook and its really new idea for me.
    I wonder what will happened if i will not use one of the Starters?
    Otherwise, do u have more ideas for Starters?
    Thank alot !

    1. You don’t have to use a starter but you’d need to replace with a salt brine to ensure you keep putrifying bacteria away, especially if you’d like to ferment for longer than 24 hours.

  2. Hi I made a small batch of this fermented porridge for four days with filtered water and Kombucha. The jar (a LeParfait type) was clean, sealed and kept in a dark place. The finished product looked like your jar above, and smelled fine (nothing off, sour or spoiled). I tipped out the soaking liquied and rinsed the oats with fresh water and cooked them for a few minutes, and they tasted fine. But I still wonder if it’s really safe and am now a bit nervous about potentially getting botulism or some other food-borne illness. Thanks in advance.

    1. Hi tina,

      If you have followed the recipe as is you do not need to worry. The kombucha is what keeps this safe, ensuring any putrefying or dangerous bacteria cannot grow. Botulism is easy to avoid when you know how, and this is why we create an acidic medium by using the starter culture (like kombucha). By following this method we are creating an environment where botulism cannot survive. Botulism is more of a risk when canning low acid foods, and so long as you follow a fermenting recipe and use the recommended amount of salt or acidic medium (like you have used kombucha) you are safe!

  3. Thanks for the post. I’d love to try it out, but the ‘poisoning myself’ is also in my head lol.

    I know it already mentions in the post that you can either strain the soaking/fermenting water or just eat it along with the oats, and that both is fine, what would you recommend tho, is it nicer, tastier and or better for you to eat it, or do you prefer to strain it and use fresh liqued for cooking.

    A second question, also already noted that you haven’t tried store bought yogurt. But was wondering if you think it would work with soy yogurt? (I don’t eat dairy) . Or are there any other good plantbased options to use as a starter culture, as you mention apple cider, isn’t the best option because the flavour it leaves behind..

    Many thanks

    1. Hi Claire,

      Personally I do not strain the oats as I like to consume the magnesium-rich milky part omitted from the oats, and adding the fresh flour in deactivates the phrase anyway.

      I love making this with coconut water kefir- plant based and my preferred starter. Just get a really active one that is unpasteurised. Homemade is even better.

  4. This article was just what I was looking for as most fermented oat recipes don’t include the added phytase enzyme! Is it possible to safely keep feeding and using the same pot? How would I do that? Thank you!

    1. Glad to help! In theory you could but it would get a bit tricky knowing how strong your first batch was (and if it is enough to make the next batch safe). Does that make sense?

  5. I naturally ferment my oats. I never include a starter, the bubbles appear after 4 days, I just keep adding rolled oats, mix them in, then wait a further 2 days and extract and eat. WHY do you COOK your fermented oats? this kills all the beneficial bacterial which has developed through the fermentation stage, its brainless if you are wanting the probiotic benefits, i can understand reducing the other non health components of the oat, But, eat them raw

    1. Pretty sure I’ve answered this extensively in the blog post, so I’d recommend reading that. Fermenting and cooking oats is a traditional process, and has many benefits. Fermenting the oats has nothing to do with adding probiotics into your diet- but, you can read this in the post.

  6. I’d like to try with coconut yogurt because I cannot have dairy at the moment, and am more likely to use it ongoing than coconut water kefir. Do you have any thoughts on this, anything I should consider?

    1. Hi Dani,

      Hi Dani. Great question. From my experience I am yet to find a coconut yoghurt that has been strong enough to work, unless its homemade. However, if you find a very active, tart coconut yoghurt you should try it. Another great alternative if you don’t have any of the recommended starters is unpasteurised apple cider vinegar- 2 Tbsp for this recipe should be enough to give some fermentation.

      Otherwise, could you ask around in your community for sourdough starter?

      let me know how you go. X jade

  7. Hi,

    Could you tel me the temperature (min-max) when fermenting (Secure the lid and leave in a dark but warm area to ferment for 1-5 days.) ?

    Thank you in advance.


    1. Hi Monique,

      Ideally around 25-30 C. In winter when it’s colder, it’ll still ferment at a lower rate. In summer, fermentation might be done after 24 hours.

      I like to create a warm spot (my oven with just the light turned on) for this purpose. It’s around 25C, and I can ferment for 2-3 days to get the sourness I like.

      Hope that helps,


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