RECIPE: #StayHome sourdough starter [v]

Bubbly Sourdough Starter

In these, the end times, the best kinds of activities are low and slow activities. Sourdough bread and its myriad ancillary tasks might just be the lowest and slowest of them all. In this post, I will take you through a week-long process that converts a lifeless slurry of flour and water into a powerful, floury jarred beast hell-bent on excreting CO2 and ethanol. Yum.

Day 1

Find a clear jar with a loose-fitting lid. The best jars in which to store a sourdough starter are a 1-litre clip-top Kilner jar with its rubber seal removed, or an 850ml Weck jar with a disc-shaped glass lid that just sits on top rather than fastening down. A large jam jar with the lid placed on top rather than screwed down will also be fine (this is what I’m currently using).

Add to this jar 150g of high protein flour, and 150g of room temperature water. Mix this together thoroughly to create a smooth paste. I’m currently using wholemeal wheat flour packing 11g of protein per 100g.

Leave this jar of paste out at room temperature overnight. Make sure the seal around the top is not airtight – we want to be in that sweet spot where any natural yeasts present in the air might find their way into the mixture, without allowing the mixture to dry out.

Day 2

Check for any activity. If the atmosphere around the jar was high in natural yeasts or they were already present within the flour, you may have a few bubbles on the surface or a little slick of water sitting on top of the paste.

Add a further 100g of flour and 100g of water. Your jar is probably over 50% full by this point, but that’s OK. What we’re trying to do on day 2 is nurture any natural yeasts that have taken hold in the mixture, convincing them that your jar is an idyllic place to live and to reproduce.

Once again, leave your jar out at room temperature overnight with a loose lid.

Day 3

You should see some activity on the surface by day 3, and maybe some small bubbles trapped in the depths of your mixture. This is a good sign, but don’t worry if there’s still nothing – it’s just a matter of time.

If you still have lots of space in your jar, and no discernible activity, add 100g of flour and 100g of water to your mixture, mix thoroughly and leave for another day.

If your mixture is starting to look alive, or your container is getting full, you will need to start discarding some of your mixture before refreshing.

At this point, decant your entire mixture into a separate container temporarily, and give your starter jar a clean. Return 150g of the starter to the clean jar, and add 100g of flour and 100g of water. Mix thoroughly, and leave out at room temperature with a loose lid.


Day 4

Bubbly Sourdough Starter

There should be an undeniable level of activity by day 4. What we want to do from this point onwards is strengthen the yeasts we’ve collected, so that a smaller proportion of them are able to grow as quickly and voraciously as possible into the same 100g measurements of flour and water. This energy is what will eventually give your bread dough a beautiful rise.

Decant all of your starter and optionally give your starter jar another clean. Pour back in 100g of starter, and add 100g of flour and 100g of water.

You now have a fully operational 300g starter. When you don’t have any baking planned, these proportions are how you will want to be refreshing your starter on a daily basis.

Day 5

Assuming you’ve noticed at least a 20% expansion of the mixture since its last feed (as above), by day 5 you can move onto strengthening your starter. If not, refresh again, keeping the measurements at 100g starter, 100g flour, 100g water for another day. Mix thoroughly, and leave out at room temperature with a loose lid so that the gases can escape.

Having seen a strong expansion from the mixture since its last feed, you can reduce the amount of starter you reintroduce after you’ve decanted it all and cleaned your jar. Try 75g starter, 100g flour, 100g water. Mix thoroughly, leave out at room temperature with a loose lid.

Day 6

If 75g of starter, 100g flour and 100g water went well, on day 6 you can drop down to 50g starter, 100g flour, 100g water. Powerful yeasts that explode into action at these proportions are what you want to use for baking. If your mixture expands to at least double its size before shrinking back down again, you are now the proud owner of a fully active starter that is ready for baking!


When not baking, you can store your starter in the fridge to lower the maintenance. Whilst still at room temperature, give it a refresh at 100g starter, 100g flour, 100g water, allow it to bubble up, then get it in the fridge. It will lose its activity, and go into hibernation. It can stay fridged for a good week.

When you’re ready to use it again, bring it back up to room temperature, and after a few hours refresh it at 100g starter, 100g flour and 100g water. The next day you can start reducing the amount of starter as above to strengthen it for baking.

What to do with all that discarded mixture?

You can add a teaspoon of sugar and half a teaspoon of salt to your otherwise-discarded starter, give it a good mix, and pour into a hot, buttery pan to create tasty little fermented pikelets.