science of breadmaking

• sifting the flour: introduces air which acts as a raising agent and helps bread to rise in the oven
• adding warm liquid: hydrates the flour, provides the moisture needed for a soft dough, provides the optimum temperature for yeast to ferment and produce the raising agent CO2, sugars are produced by this fermentation, which the yeast consumes
• mixing and kneading dough: the two proteins present in flour (glutenin and gliadin) become hydrated, produces an elastic protein complex called gluten, gives bread its structure and prevents it from collapsing
• proving dough: some of the starch present in flour is broken down and fermented by yeast, CO2 is produced and trapped in pockets which causes the gluten network to expand and therefore makes the dough rise
• knocking back: removes the large CO2 bubbles produced by the yeast, to even the texture and create a better rise
• baking: the bread dough rises as the CO2 produced by the fermentation of yeast expands with heat, yeast activity increases at first but as the temperature rises more and more it slows down until the heat kills the yeast, the water is absorbed by the starch granules in the flour which swell and gelatinise and support the firm structure of the loaf, the gluten strands are stretched as the CO2 expands and results in the finished bread structure, steam, CO2 and alcohol are released, dextrin is formed on the outside and gives bread its colour