Cultivate a starter

Sourdough forms the basis for doughs with long fermentation times, especially for those in which a lot of rye flour is processed. The sourdough improves the baking properties of rye-heavy bread, ensures a typical nutty-sour taste and increases the shelf life of the bread.

What you need

  • 1 large, lockable container (at least 2.5l capacity)
  • 500-600g wholemeal rye flour
  • 500-600g water (40–45 °C)
  • 5-7 days


  • The ideal temperature for the fermentation process is achieved in the oven (switched off, light on) with the door slightly open (temperature 26-28 °C)
  • Day 1: mix 100g water and 100g flour and let ferment for 12 hours
  • After 12 hours stir the mixture with a spoon
  • Day 2: after 24 hours, add 100g water and 100g flour to the mixture, stir
  • After 12 hours stir the mixture with a spoon
  • Days 3 to 6: repeat steps from day 2
  • When the mass has already increased its volume significantly after 12 hours, is visibly streaked with bubbles and smells slightly sour, the starter is ready
  • Remove 100g from the finished mass and place in the refrigerator, sealed; freshen up after 7 days (see “Maintaining a starter”)
  • The rest of the mixture can be used as preferment to make a bread (see the basic recipe for the rye-wheat bread)

Tips & tricks

  • In the course of the cultivation process, the fermentation can cause the sourdough to smell quite unpleasant in some cases or it can exude fusel alcohol; however, after 5 days at the latest, a slightly sour smell should prevail
  • Make sure that no foreign bacteria impair the ripening process (rinse the bowl thoroughly with boiling water beforehand; close the lid tightly); if there is a putrid smell or a brownish-greenish discoloration of the mass becomes visible, the dough has been contaminated and must be disposed of
  • The cultivation can also be done with half of the ingredients, i.e. 50g water/flour per day; then an additional day should be planned for fermentation