A sourdough starter is a little pot of bubbly goodness that turns a lump of bread dough into a beautifully risen loaf which is tangy and delicious. When you cook with sourdough, you don’t need to use any commercial yeast to make your bread rise.
That’s because sourdough starter contains wild yeast, which acts as a substitute. If it sounds complicated, then be assured that making one is really easy. You simply add flour and water to a jar, leave it alone, and wild yeast — which is found in the air around us — populates the mixture along with bacteria, turning it into a live culture. You add a small amount of this mixture to bread dough and it makes the bread rise. It is how people have made bread for thousands of years.
Commercial yeast is designed to make bread rise as quickly as possible. Sourdough fermentation is a slower process, but it produces loaves with a completely unique chewiness and depth of flavour.
Once you have a starter up and running, you need to feed it regularly with more flour and water to keep it happy and bubbly. Theoretically, it can live forever, and one you create now can still be giving you beautiful loaves of bread years from now. Think of it as a low maintenance pet.
Creating a starter is probably the most intimidating part of the whole process. There are hundreds of accounts of how best to do it in recipe books and on the internet, along with all sorts of tricks and suggestions.