Video: Baking – The art and science of bread

Paul Rhodes guides us through the process of making thousands of cakes, rolls and loaves of bread every day

As an artisan baker, Paul uses very traditional methods and ingredients  just flour, water, salt and specially manufactured yeast are used to create his delicious bread.

Other types of industrial bakers focus on high speed and fast output; they use additional ‘improvers’ such as amylase, an enzyme that accelerates the breakdown of more complex carbohydrates within the flour (such as starch) to simpler sugars that the yeast can then metabolise.

Yeast is crucial for good bread. By providing it with a rich source of food – the flour – and the perfect temperature, around 24–26°C, this single-celled eukaryotic organism (scientifically known as Saccharomyces cerevisiae) enthusiastically gets to the business of eating. As yeast consumes sugars, fermentation begins, producing ethanol, an alcohol, and carbon dioxide, a gas. At these warm temperatures molecules of ethanol will quickly evaporate into the air, but the carbon dioxide gas becomes trapped within the structure of the dough, causing it to expand and rise.

The structure of bread, its overall texture and solidity, is largely determined by the presence of gluten (Latin for ‘glue’), the name given to protein bundles naturally present within the flour. These proteins allow the flour to develop a cross-linked structure, further aided by kneading – repeatedly pressing, stretching and folding the dough – helping trap carbon dioxide gas as it’s produced by the yeast.

Because artisan bakers don’t add enzymes to their dough, they’ll often leave their bread to sit ‘proofing’ twice, allowing as much time as possible for the yeast to do its work, adding texture and flavour to the dough. Finally, the dough is placed in hot ovens, killing the yeast and resulting in one of the best-known foods there is. Paul doesn’t use chemical preservatives (just a little extra-virgin olive oil); his bread is baked fresh every day and, judging by demand, eaten just as quickly.

Running time 3 min 47 secs

Downloadable resources

About this resource

This resource was first published in ‘Careers From Biology’ in June 2011 and reviewed and updated in November 2017.

Careers From Biology, Food and Diet
Education levels:
16–19, Undergraduate, Continuing professional development