In 1988, Alsatian chemist Hervé This and Hungarian scientist Nicolas Kurti coined the term molecular gastronomy to examine the science behind what we're cooking. As Kurti once noted, we knew more about the temperature of Venus than we did of souffles (though that would change when Kurti himself measured it).
Molecular gastronomy is a scientific discipline -- seeking to understand how methods of cooking change foods. What is really happening during cooking? What makes a hard-boiled egg ... hard? And how can we use this technical or scientific knowledge to understand the social and artistic qualities of cooking?
Strictly speaking, molecular gastronomy is a part of food science, but the focus is somewhat different.
Food scientists and food chemists may develop new ingredients, but nearly always with the goal to produce nutritious foods for the mass market. Those involved with molecular gastronomy are more interested in investigating the transformations done by cooking that happen in the home or on a smaller scale.
Chefs have used this increased understanding of the chemistry and physics involved in cooking to develop new and exciting foods -- and even new experiences in dining. Grant Achatz, chef at the four-star and famously avant-garde restaurant Alinea in Chicago, uses scientific techniques and tools to create new methods of preparing and presenting food. He even fashions new tools and utensils just for his food artistry.
This style of haute cuisine has been called "Experimental Cuisine", "Avant-Garde Cuisine", "Molecular Cooking", and other terms.
Culinary colleges have followed this trend, with courses on more scientific techniques of cooking, such as low-temperature sous-vide or the use of liquid nitrogen. The French Culinary Institute's Cooking Issues blog goes into detail about new experiments using technology in cooking.
To some extent, molecular gastronomy has made the mainstream. In fact, the Research Chefs Association's Culinology(R) program is all about the "blending of the culinary arts and the science of food". And the FoodNetwork's popular "Good Eats with Alton Brown" program often uses quirky explanations of the science behind cooking to make recipes memorable.
The future of molecular gastronomy as a field of scientific inquiry (and even as a term) has been hotly debated by food scientists and culinarians alike. But both camps agree that understanding the science behind cooking can lead to new, even better, foods that could improve the health and wellness of people anywhere.