What is a Sourdough Starter
A sourdough starter is how we cultivate the wild yeast in a form that we can use for baking. Since wild yeast are present in all flour, the easiest way to make a starter is simply by combining flour and water and letting it sit for several days.
Making a starter is a simple process of combining flour and water, which is then subsequently ‘fed’ or refreshed with more flour and water over a period to encourage the yeast to ferment and the bacteria to develop.
Once established, your starter will go through a predictable cycle of bubbling, growing to about double its size, and then falling, and will take a similar time to complete this cycle if held at a consistent temperature.
How To Make Your Own Sourdough Starter
Click here for a step by step guide to making your own sourdough starter.
Yeast is present on the surface of cereal (eg wheat, rye) grains. When those grains are crushed to flour, and that flour is then mixed with water, the yeast will begin to multiply and thrive. As the yeast feed on the flour, they produce carbon dioxide gas.
Over time, if more flour and water are provided, and the mixture is ‘refreshed’, the yeast colony will become more concentrated. Eventually, the mixture will produce enough gas that, on adding it to a dough, it will raise that dough to form bread.
Alongside yeast, bacteria also thrive in the mixture. Those which are beneficial to sourdough making, including lactic and acetic acid bacteria, will multiply well alongside the yeasts present.
These bacteria produce acids that contribute to the flavour and texture of sourdough breads. These acids may also help preserve breads made with the mixture, lengthening its shelf life.
Starters are often referred to as a percentage ‘hydration’, for example 100% hydration sourdough starter. The percentage indicates the hydration of the flour in the starter.
For example, a 100% hydration starter would be made from and fed with equal quantities (by weight) of both flour and water, or 1 part flour and 1 part water.
The hydration of a starter not only affects its consistency but also how quickly it will ferment. A less hydrated starter will be thicker and slower to ferment, hence requiring less feeding.
Feeding your sourdough starter
Once your sourdough starter is established, healthy and strong (and doubling in at least 8 hours when at room temperature), it will need to be ‘fed’ regularly to be kept active and to maintain its ‘strength’. If not fed regularly with fresh water and flour, the natural yeast within the starter will run out of food and ultimately die.
A mature and strong starter will have more flexibility and will be more resilient to changes than a young starter so don’t worry too much if you occasionally miss a feeding by a day or so or if your quantities are slightly out – just get back on track as soon as you can and your starter will bounce back.
To feed your starter, firstly use a clean utensil to remove all but 100g of the starter from the jar. Then add 100g flour and 100g water and stir well until evenly combined. Seal the jar and store at room temperature or in the fridge.
You now have 300g of starter.
Storing your sourdough starter
A sourdough starter can either be kept at room temperature or in the fridge.
If you aren’t intending to use your sourdough starter every day, it is best kept in the fridge. To do this, feed it as instructed above, seal the jar and then stand at room temperature for 2-3 hours (to help reinvigorate the yeast) before placing in the fridge to store.
A starter stored in the fridge will only require feeding once a week to maintain it.
If you use your starter every day, keep it at room temperature. Follow the feeding instructions above and then leave it at room temperature. You will need to ‘feed’ it every day (at the same time, if possible).
A starter stored at room temperature and fed everyday will have a milder flavour than one kept in the fridge and fed once a week.
Got water on the top?
If a grey-like liquid forms on top of your sourdough starter, this is an indication that an excess of alcohol has been produced as a by-product of the yeast fermentation. It often appears if the sourdough starter is ‘hungry’ because it has been left for longer periods of time without feeding or if it requires more frequent feeding.
If there is only a thin layer, you can either stir this liquid back into the sourdough starter or drain it away before feeding it again. If you stir it through, it will add a more intense flavour to your sourdough starter and, in turn, your sourdough bread.
If there is a thick layer, it is best to discard it before feeding.
Using your sourdough starter
When you want to use your sourdough starter in a recipe, feed it and stand at room temperature for 4-8 hours before you intend using it. It should at least double in volume and bubbles will start breaking the surface in this time, which will indicate that it is strong and ‘active’ enough to use. The time will vary depending on whether it has been stored in the fridge and the temperature at which it is standing. If it doesn’t, repeat the feeding and standing process until it does.
Remove the amount you require for the recipe and then repeat the feeding process and either stand at room temperature to use again or transfer to the fridge to store.
Once your starter is ready to use, this Basic sourdough bread recipe is a well-tested recipe to begin your sourdough baking.
Flour salt and water
Made with the simple basic ingredients of flour, water and salt; there are three distinct stages to making a sourdough loaf (1) The Starter (2) The Ferment and (3) The Dough itself.
A little bit about this site
I want to offer and share information, tips, techniques, recipes and tools for the home baker, with an above average interest in the art of sourdough bread making.