Gastronomy is the art or science of food eating. Also, it can be defined as the study of food and culture, with a particular focus on gourmet cuisine. One who is well versed in gastronomy is called a gastronome, while a gastronomist is one who unites theory and practice in the study of gastronomy.
Etymologically, the word "gastronomy" is derived from Ancient Greek γαστήρ (gastér) "stomach", and νόμος (nómos) "laws that govern", and therefore literally means "the art or law of regulating the stomach." The term is purposely all-encompassing: it subsumes all of cooking technique, nutritional facts, food science, and everything that has to do with palatability plus applications of taste and smell as human ingestion of foodstuffs goes.
Gastronomy involves discovering, tasting, experiencing, researching, understanding and writing about food preparation and the sensory qualities of human nutrition as a whole. It also studies how nutrition interfaces with the broader culture. Later on, the application of biological and chemical knowledge to cooking has become known as molecular gastronomy, yet gastronomy covers a much broader, interdisciplinary ground.
The culinary term appears for the first time in a title in a poem by Joseph Berchoux in 1801 , "Gastronomie".
The derivative Gourmet has come into use since the publication of the book by Brillat-Savarin, "The Physiology of Taste". According to Brillat-Savarin: "Gastronomy is the knowledge and understanding of all that relates to man as he eats. Its purpose is to ensure the conservation of men, using the best food possible."

en.wikipedia.org/wiki/Gastronomy