My favourite subject at school was chemistry but I never imagined that one particular biochemical reaction would dominate my career. Yet so it has proved. And that almost magical natural event is called fermentation. It shows how what we learn in the classroom can play an unexpected role in adult life.
This fantastic process underlies the production of not just alcohol, but bread too – and indeed pizza. Under anaerobic conditions, certain single-cell fungi called yeast will convert carbohydrates into a variety of products. For bread the dough is leavened with baker’s yeast, then allowed to rise (or proofed). This step releases carbon dioxide into the dough, as well as a complex mix of other compounds such as ketones, alcohols, aldehydes and esters. Many of these are evaporated by subsequent baking. Others impart particular flavours and consistency to the crust and crumb of the bread.
There is something transcendent in seeing flour transformed via fermentation and baking into a delicious loaf, be it a ciabatta, baguette or bloomer. Bakers at both my companies Patisserie Valerie and Gail’s take simple ingredients and transform them into delicacies produced via fermentation, ranging from croissants to muffins to cupcakes. And I have been involved with countless restaurants, from PizzaExpress to Rocket, that take flour, water, yeast, salt, cheese and tomato and transmute them into enticing pizza.