From Newton to crouton: the science of cooking
Most people who cook take a practical approach: watching to see when a sauce thickens up, when bread rises perfectly and how long it takes to scramble eggs. We learn by trial and error, from each other and from recipe books. But how many of us know what is really going on when we cook, in scientific terms? Some famous chefs, most notably Ferrán Adria of top restaurant El Bulli and Heston Blumenthal, have taken a scientific approach to cooking, turning the kitchen into a laboratory and producing some novel and astonishing results. Some of this pioneering work has now been absorbed into standard cordon bleu chef curricula and has become mainstream in high-end restaurants.
A free course from Harvard University on edx.org brings some of this science to the masses. It is a suitable course for non-scientists to improve their culinary knowledge, as well as physics and chemistry students who like the idea of being able to eat the results of their lab experiments.
It teaches the scientific concepts that underlie everyday cooking and haute cuisine techniques and how to apply principles of physics, chemistry and engineering to cooking. Students are encouraged to head into their own kitchens to put the science to the test.
The teachers are a Professor of Applied Mathematics and Applied Physics, a Professor of Physics and Applied Physics, and a Preceptor in Science and Cooking, all bona fide Harvard boffins. Over the six weeks of this eLearning course, they impart a feast of science-based cooking knowledge.
Molecules, moles, flavour and pH are covered in Week 1. What are the major macromolecules of food that gives us the tastes we know and love, and how do they form in the process of cooking?
Next are energy, temperature and heat. This includes a scientific discussion of how to cook the perfect egg, and delves into what temperature does to the internal structure of food.
Phase transitions arrive in Week 3. The reasoning behind techniques such as sous vide and rotary evaporation is explained, and how they use phase transitions – the transformation from solid to liquid to gas – to achieve the desired effects.
Week 4 looks at diffusion and spherification, gelling agents and how they are are used to dehydrate foods to concentrate the flavours and produce exciting results.
Week 5 covers heat transfer and examines cooking to perfect steak, the perfect burger and the perfect french fries. This week also discusses the Maillard reaction, which causes browning of meat and makes it super-tasty.
The final week is all about candy. The stages of sugar, the solubility of ingredients and how they lead to the ideal mouth feel are discussed, as well as the science of tempering chocolate to make it stiff and crunchy to the desired degree.
The course is free on edx.org. The burning question, of course, is should you wear an apron or a lab coat?