One of the most important elements in baking sourdough at home is having a good sourdough starter. You may have heard stories of people jealously guarding and nurturing their starter, naming it, carefully feeding it and controlling the temperature and environment it lives in. In truth, this makes it sound a lot more complicated than it is.
A sourdough starter is simply a mixture of flour and water – combining the two activates the wild yeasts and bacterial spores naturally found in flour. And, given time, these microorganisms become strong enough to make the bread rise.
All sourdough starters follow the same process. Yeast eats sugar present in the carbohydrates (the flour). This creates lactic and acetic acid (the sour taste in sourdough) and carbon dioxide. The latter gets trapped in the dough’s gluten structure, creating little bubbles that make the dough rise. Every time the starter is fed, this little army of yeast gets stronger and more populated. The stronger the sourdough starter, the better the bread.
Sourdough starter ingredients and equipment
A glass flip-top jar makes a good vessel for a starter – when it’s out at room temperature, the lid can be left slightly open to release excess gas, and then shut again while it’s in the fridge.
I use a mix of strong white bread flour and rye flour for feeding my starter. Strong white bread flour has strong gluten bonds, meaning it can sustain its structure as it bubbles, while rye flour has a high sugar content, so the starter is well fed. Good digital scales are a must when feeding the starter, to ensure you are feeding it with exactly equal parts flour and water.
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- strong white bread flour 25g
- rye flour 25g
- warm-to-the-touch water 50g
How to store sourdough starter
When not using the starter, it’s best to keep it in the fridge – this drastically reduces its activity. If I’m not baking at all that week, I will feed the starter with 50g flour and 50g water, and put it back in the fridge. This will give it enough food to keep it alive while it’s not being used.
As long as its been kept in the fridge your starter should be revivable after several weeks of neglect. No need to drop your starter into a hotel (these really do exist), just pour off any clear liquid, give it a feed and leave at room temperature. If after one feed you’re not getting many bubbles, feed again and leave it out. If there’s still no movement, it may be time to make a new starter.
When preparing to bake a loaf, the night before I need to make my dough I will remove my starter from the fridge, feed it, and leave it out at room temperature to bubble up and get its strength back.
Remember to always feed the starter with more flour and water than is needed for the bake, so that there is enough left over to be used in the future.