Rye Sourdough Starter

In a clean glass jar with loose-fitting lid, combine 50g whole rye flour (50g) and 50g lukewarm water (50g) (at around 24–27°C) (at around 24–27°C). Stir well with the spoon for mixing until you have a thick paste. Cover the jar loosely (so air can still get in) and leave it at 22–26°C. On this first day, the mixture begins to hydrate and attract wild yeast and bacteria from the flour and the air. It may not look like much is happening yet — that’s normal.

Check your jar. You might see a few small bubbles or a faint sour smell, but don’t worry if nothing seems active yet. Stir the mixture well with the spoon for mixing to release gas and refresh the surface. Then feed it: add 50g whole rye flour (50g) and 50g lukewarm water (50g) (at around 24–27°C), stir until smooth, and cover loosely again. Leave at 22–26°C. The microbes are slowly waking up and multiplying.

By now, you should notice bubbles, a tangy aroma, or slight rising. Today you’ll start the routine of discarding and feeding. Scoop out and discard about half of the starter (this keeps the acidity balanced and prevents overflow). Then add 50g whole rye flour (50g) and 50g lukewarm water (50g) to the remaining starter. Stir well, cover, and let it sit at 22–26°C. The culture is becoming more active, and a steady feeding routine helps it grow stronger.

Your starter should now be noticeably active, with bubbles throughout and a sour, fruity smell. Repeat the routine: discard half, then feed with 50g whole rye flour (50g) and 50g lukewarm water (50g). The starter should now rise higher and fall back after feeding — a sign of healthy fermentation. Keep it at 22–26°C.

By now, your starter should double in size within 6–8 hours after feeding. Discard half and feed with 50g whole rye flour (50g) and 50g lukewarm water (50g) again. The smell should be pleasantly tangy and slightly yeasty. Keep it at 22–26°C. Your culture is stabilizing, with yeast and bacteria now in balance.

Feed your starter as usual (discard and refresh with 50g whole rye flour (50g) and 50g lukewarm water (50g)). It should now reliably double or even triple after feeding. The texture should be airy and sponge-like when stirred. Keep it at 22–26°C. Your starter is nearly mature and ready for baking.

By now, your starter should reliably double in 4–6 hours after feeding, with a balanced sour aroma. Feed it one last time with 50g whole rye flour (50g) and 50g lukewarm water (50g). Congratulations — you now have a mature sourdough starter! It’s ready to be used for baking or stored for weekly maintenance.

To reduce hassle, you can store your starter in the fridge. Once a week, take it out, discard about half, and refresh with 50g whole rye flour (50g) and 50g lukewarm water (50g). Stir and leave at 22–26°C for 4–6 hours until it becomes active again, then return it to the fridge. This keeps your starter alive with minimal effort while slowing its fermentation.

Your whole rye flour (50g) sourdough starter can now be used to make naturally leavened pizza doughs. Before baking, take a portion of starter and feed it to build strength. Once it doubles and is full of bubbles, use it in your dough. For full step-by-step instructions, refer to the sourdough pizza recipes featured in Napo, where you’ll learn exact quantities and fermentation times tailored for pizza.