What is sourdough, and why does everyone talk about it?
9 August 2026·1 min read·Bakery team
A starter that is nothing but flour and water changes both the taste of bread and how it sits with you. A short account from the bench.
Sourdough begins when flour and water meet the microorganisms already in the flour and in the air. There is no commercial yeast in it; the work is done by lactic acid bacteria and wild yeasts together.
Where the flavour comes from
Commercial yeast raises a dough in an hour. Sourdough wants 12 to 24. In that long window the bacteria produce lactic and acetic acid — which is exactly the faintly sour, caramel note in the finished loaf.
The digestion question
Long fermentation breaks down part of the phytic acid in wheat and pre-digests some of the starch. For someone with coeliac disease this is not a solution. But most people who say "bread sits heavily with me" do not say it about sourdough.
If you want to try at home
Put 50 g wholemeal flour and 50 g water in a jar. Every day at the same hour, throw half away and feed it the same amount of flour and water again. Somewhere between day five and day seven it will start to rise and smell fruity. That is your starter.
Ours is four years old and gets fed from the same jar every morning.
- #sourdough
- #bread