The flour we use, and why it matters

A sourdough loaf is flour, water and salt. There is nowhere to hide. No sugar, no oil, no improvers, no dough conditioners — so the character of the bread is very largely the character of the flour that went into it.

We bake with Gideon Mills Stoneground White Bread Wheat Flour and their Stoneground Whole Wheat Flour.

Stoneground matters. Industrial roller milling separates the wheat kernel into its parts at high speed, and the heat and shear of that process strips out much of what gives wheat its flavour. Stone milling crushes the whole kernel more slowly and at lower temperatures, so more of the germ and the oils it carries stay in the flour. You can smell the difference in a bag of it, long before it becomes dough.

The two flours behave differently, and that is the point. The white bread flour has the gluten strength to trap gas through a long fermentation, which is what gives you a light, open crumb and a loaf that stands up tall rather than spreading. It is the structure of the loaf.

Whole wheat brings the bran and the germ, and with them a deeper, nuttier, faintly sweet flavour. It also ferments faster, because the bran carries more of the wild yeast and bacteria's food supply. But bran is sharp at a microscopic level, and too much of it cuts the gluten strands as they form — which is why a hundred percent whole wheat loaf is typically denser and tighter than a white one.

So the proportion between them is a decision, not an accident. Lean white and you get height, openness and a mild, clean flavour. Lean whole wheat and you get colour, depth and a closer crumb. We bake to a ratio we have settled on over many, many bakes, and we keep it consistent so that the loaf you collect this Friday is the loaf you collected last Friday.

Good flour costs more than commodity flour. We think it is the least skippable expense in the whole operation, because it is the one thing a long ferment cannot compensate for.