Learning how to increase your sourdough starter means you don't have to keep loads of sourdough starter on hand to bake sourdough.
You can keep a small sourdough starter (between 25-50g of starter) on hand and "build" or "scale" your starter when you want to use it.
This blog will help you to understand the following:
- How to increase your sourdough starter from a smaller amount to a larger amount
- Increasing the amount of sourdough starter you have on hand for a specific recipe
- Using a bigger sourdough starter feeding ratio to increase the weight of sourdough starter
Understanding Sourdough Starter Ratios to Increase Amount of Starter
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). It's always written in this order.
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.
How To Increase Your Sourdough Starter
In order to increase your sourdough starter, you need to work out exactly how much you want to end up with first. Let's use 200g for this example.
Now, divide this number by 2. This will give you the equal amounts of flour and water that you need to add to your sourdough starter to increase the amount you have.
Then you would add this amount to the smaller amount of starter you already have.
When you remove the 200g from the jar to do your baking, you'll be left with some residual starter. You can then feed this ready for your next bake.
Let's look at an example.
Example of How To Increase Your Sourdough Starter
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 100g of each flour and water to that starter to make 200g (because 200g divided by 2 is 100g).
This will mean you will have 250g of starter in your jar when it peaks because you've added 100g of flour and 100g of water to 50g of starter.
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.
Make More Sourdough Starter Using 1:1:1 Ratio
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 200g of starter, 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 of sourdough starter.
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.
But at the end of fermentation - your starter would weigh 210g because 10g of starter plus 100g of flour and 100g of water.
You can build a much bigger starter from just a small amount very easily (as above) - 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 When Increasing the Amount
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 Sourdough Starter Different Ratios
You can feed your starter a different ratio if you want to. Feed your starter 1:2:1 which means you'd feed it twice as much flour as water.
This 1:2:1 ration can be handy if you are trying to strengthen your sourdough starter. It will decrease the hydration though, so it's often something you just do for a few days.
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. It may like a little less hydration. Experiment and see what works for your starter.
Isn't it amazing that all of our sourdough starters are completely unique!
When increasing the size of your sourdough starter, make sure you are using a big enough jar.
Further Reading
If you're interested in reading more on this topic:
- Differences between a Levain and a Sourdough Starter
- 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.
- Looking to understand why the amount of starter in a recipe matters? You'll find an explanation here.
