Kombucha sourdough bread recipe

Kombucha sourdough bread finished loaves & crumbThis successful experiment could revolutionise my baking. It means that I can bake sourdough bread in 24 hours without the need to keep an active leaven refreshed.

The bread is gloriously moist and chewy as sourdough should be. This has a big malty wholemeal taste with a rich, crisp crust. It’s not at all sharp or tangy, I know I can make a more ‘sour’ loaf if I use an overnight fridge retard to extend the fermentation time.

If you’d like to find out what I did and how to make this bread, please read on.

Kombucha Sourdough Bread Recipe

I used the kombucha to activate a flour ‘poolish’, sponge or batter. I then used this to start the dough fermenting.

Kombucha is a ‘symbiotic culture of bacteria & yeast’ or SCOBY. The yeasts (some used in baking & brewing) ferment the sugar into alcohol which the acetobacter and other bacteria convert into acetic and (supposedly healthy) gluconic acid. The SCOBY is a mat of cellulose material. I mostly use this to ferment a sweet tea to make a drink. The drink tastes good and is reputed to have health benefits. I’ve also used it to make vinegar.

I have a constant supply of kombucha going, I brew 5 litre and 10 litre batches in turn. I used kombucha that was still easy to drink as it was not very sour. This means that the liquid itself still has some sugars in it and it hasn’t exhausted the ‘food’ available to it. I guessed that this would mean the leaven would start more quickly and would not taste very sour from the start.

In the poolish, I used coarse wholemeal flour for flavour and to give the SCOBY plenty of nice stuff to eat. I used the rye flour partly for flavour but mostly for food for the SCOBY to get a quick start to the ferment. You could use what flour you wish, obviously it will affect the final colour, texture and taste of the bread.

I used some honey to make sure there were some very easily available sugars for the SCOBY to find.

I used a ratio of twice the weight of flour to liquid. My normal leaven has an equal weight of flour/liquid. I increased the ratio here to make a more liquid leaven that should get going more quickly than a firmer one.


For the poolish

150g course wholemeal flour
50g wholemeal rye flour
30g runny honey (blitz in microwave for 10-15 seconds if it’s hard)
300g active kombucha tea (not too sour)

For the dough

860g strong white flour
440g warm water
18g fine sea salt

This produces about 1.8kg of dough, enough for two large loaves.


The night before you want to bake mix the ingredients for the poolish. Cover with a tea towel, muslin or a plastic bag and leave in a warm place. I put mine on a seed propagator that was on and maintains a temperature of about 22°C.

Here’s what I had the next morning.
Kombucha bread leavenYou can see it’s nicely bubbling, and some of the liquid has begun to separate from the flour. I tasted the poolish and it was a very palatable sweet, wholemeal porridge.

Mix the poolish with the rest of the dough ingredients in a big bowl until you have something like this.
Kombucha bread doughCover and leave in a warm place. Do four stretch and folds of the dough at about hourly intervals, as in the first video in my how to make sourdough post.

Then split the dough in two equal parts and shape the dough. Put into bannetons or on to floured greaseproof or Bake-o-Glide.

Allow to prove in a warm place for about 2 to 4 hours. This time really will depend on the temperature. What you want is for the gases produced by the fermenting yeasts to still have some power. When the loaf is first made, the dough is very resilient. If you press it with a finger it will push back and fill the dent. The longer you prove the less pronounced this effect is. Ideally, you will pop the loaf in the oven before the dough ceases to push back. It’s worth saying that with sourdough you will not get the dramatic ‘doubling in size’ you see in some other yeasted bread recipes. Look for a 25-50% increase

About 45-60 minutes before you bake, preheat your oven to highest setting. When you first start, judging this time won’t be easy so err on the side of being early and not late. Starting your loaf off in an oven that is not hot enough will not get you good results.

Then slash the dough in a way you find attractive and bake at 240°C for 15 minutes with a tray of boiling water in the oven (or your own steam generating method). Then remove the steam and bake for another 30-35 minutes at 190°C until you have the colour you like.

And there you have it, a very pretty and great tasting bread.

It means that I have more flexibility in how I bake. If I don’t have a very active flour & water sourdough leaven, I can still bake the next day if I choose. Obviously, if you’re not a regular kombucha brewer, you won’t have this to hand, but it’s worth thinking about.

Of course, there’s also these options:

So what’s your favourite leaven?





3 responses to “Kombucha sourdough bread recipe”

  1. narf77 Avatar

    Another use for booch! I have experimented using non-dairy kefir to leaven bread with great success and now I can use my booch as well? BONUS! And here I was thinking that I would have to soldier on with sourdough when I can have it all with a delicious loaf of bread and something beneficial to quaff with my sarnie as well 🙂 EXCELLENT share sir…top marks 🙂

  2. lindaswildlifegarden Avatar

    Awesome post I must have another go at sour dough making

  3. Julia Avatar

    Fantastic, I love that we are all finding ways to capture and harness the power of those everyday natural yeasts used in the fermenting process to make really, really great looking and tasting bread. Perfectly written and explained too. Everyone should try it! You will need to add it as an addendum to your book!