This article explores how food and drink in opera convey meaning, define relationships, trigger psychophysical reactions, and denote dramatis and singers’ personae. It proposes a basic theoretical foundation of “operatic gastromusicology” by outlining five primary functions of food in opera: social, intimate, denotative, medicinal, and dietary. These five functions are exemplified through the analysis of gastronomic signs in Verdi’s Traviata. The opera and its performance history illustrate how the production of this opera reflects the changing culture of food and the body. Luchino Visconti’s production in Milan’s La Scala in 1955, with Maria Callas as the consumptive protagonist, was in this respect a watershed in the history of opera. The singer’s rapid and prodigious weight loss prior to this performance triggered an epochal shift in opera culture toward an unprecedented conflation of the dramatis and singer’s persona.