James and Kay Salter are attuned to a universal language essential to all important food writing. Even in the briny, thickish stew recipes recorded in Richard II’s day, there were traces of a sympathetic voice. What is the nature of this food language? Does food writing require an appetizing subject? Do an experiment: Eat till you can’t take another bite, then read the Salters. What does your mind make of food when your belly is full?