You don’t have to keep loads of sourdough starter on hand to bake sourdough. You can keep between 25-50g of starter on hand and “build” or “scale” your starter when you want to use it. This blog is useful if you want to know how to increase your starter for a larger amount or for multiple recipes.
In general, your sourdough starter is made from equal amounts of flour and water, or thereabouts. This is called 100% hydration because the amount of water is equal to the amount of flour. You will see this referred to as 1:1:1 (starter:flour:water). Most sourdough recipes will use a 100% hydration starter. You may also come across stiffer starters like Pasta Madre which uses a 1:1:0.5 ratio or less.
Scaling Your Sourdough Starter – A How To Guide
If you have 50g of starter in your jar, but you would like to have 200g of starter because you want to bake a few different things then you would need to add 75g of each flour and water to that starter to make 200g. It’s best if you add just a little more, so I’d say add 100g of flour and 100g of water so that when you remove your 200g, there is still around 50g of starter left in the jar for your next build or bake.
When you’ve removed your 200g, you can just put the 50g remaining straight into the fridge, since you’ve already fed it. If you were going to leave it on the counter, you could leave it to fall before you fed it again.
You can use the 1:1:1 ratio in many situations when scaling your sourdough starter. Even if you only had 10g of starter and you wanted 100g, you’d just have to feed it at 1:10:10 which would mean adding 100g of flour and 100g of water to that 10g. This would mean that your starter would take quite a while to peak ready for baking as it has a lot of food to get through.
You can build a much bigger starter from just a small amount very easily – time is the thing that will change. For example – if you had 15g and you wanted 300g – then you would feed your 15g of starter 150g of water and 150g of flour – this way you’d have 300g of starter with a little left over for your next build/bake. Feeding your starter this amount would be equivalent to 1:10:10. It would take quite a while to peak though, so this would be another one that you would need to do overnight.
All of these examples are 100% hydration because you are feeding your starter equal amounts of flour and water.
Maturity of Your Starter
If you are using a very small amount of starter to build a much larger one, it’s better if your starter is quite mature. When your starter is developing and still quite young, you need to be feeding and discarding regularly to keep building your colonies of yeast and bacteria. Once your starter is mature and doubling very consistently, you will be able to keep much smaller amounts and then build as you need it, as explained above.
Feeding Your Starter Different Ratios
You can feed your starter a different ratio if you want to. You could choose to feed your starter 1:2:1 which means you’d feed it twice as much flour as water. You could choose to go with 1:2:2 – this is a bigger feed so it would take longer for your starter to peak. If you’re doing a 1:2:2 or a 1:3:3 ratio, you could reduce your initial starter amount from 50g to 25g so you’re not using as much flour – or if you need a lot of starter, leave it as 50g or increase to 100g. See the pattern?
Feeding your starter a different ratio can take a bit of experimentation and practice. Your starter might be at it’s happiest at 100% hydration. I have discovered through trial and error that mine likes to be fed 1:2:1. If I feed it less than this, it tells me it’s not happy by smelling like acetone very quickly.
Isn’t it amazing that all of our sourdough starters are completely unique!
If you are looking for ways to strengthen your sourdough starter, this information will be helpful.
Want to understand Baker’s Math and Baker’s Percentages? You’ll find an explanation here.
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