Great thread. Below are a dozen generalist books and a dozen academic books that I have enjoyed reading (one of the twenty-four is mine, so that one I enjoyed writing) and that have not otherwise been mentioned on this thread (I don't mention M.F.K.Fisher or George Orwell, for instance). All of the academic books are readable by non-specialists, although some more than others:
Generalist:
Diane Ackerman, A Natural History of the Senses
Nelson Algren, America Eats
Jeremy Iggers, The Garden of Eating
Leon Kass, The Hungry Soul
A. J. Liebling, Between Meals
John McPhee, Giving Good Weight (the first essay, "Giving Good Weight" and the last, "Brigand de Cuisine")
Kathy Neustadt, Clambake: A History and Celebration of an American Tradition
Jean-Francois Revel, Culture and Cuisine: A Journey Through the History of Food
Raymond Sokolov, Fading Feat: A Compendium of Disappearing Regional American Foods
Richard Sterling, The Adventure of Food: True Stories of Eating Everything
Andrew Toddhunter, A Meal Observed
Calvin Trillin, American Fried (the first of the "Tummy Trilogy")
Academic:
Warren Belasco, Appetite for Change: How the Counterculture Took on the Food Industry, 1966-1988 (American Studies)
Theodore Bestor, Tsukiji: The Fish Market at the Center fo the World (Anthropology)
Priscilla Ferguson, Accounting for Taste: The Triumph of French Cuisine (Sociology)
Gary Alan Fine, Kitchens: The Culture of Restaurant Work (Sociology)
Donna Gabaccia, We Are What We Eat: Ethnic Food and the Making of Americans (History)
Marvin Harris, Good to Eat: Riddles of Food and Culture (Anthropology)
Lisa Heldke, Exotic Appetites: Ruminations of a Food Adventurer (Philosophy)
Harvey Levenstein, Paradox of Plenty: A Social History of Eating in Modern America (American Studies)
Stephen Mennell, All Manners of Food: Eating and Taste in England and France from the Middle Ages to the Present (Sociology)
Sidney Mintz, Sweetness and Power: The Place of Sugar in Modern History (Anthropology)
Rebecca Spang, The Invention of the Restaurant: Paris and Modern Gastronomic Culture (History)
Amy Trubek, Haute Cuisine: How the French Invented the Culinary Profession (Anthropology)
Don't miss Liebling, and, among the academic books, Mintz.