Must distillation processes simulation is a challenging task, due to the lack of thermodynamic interaction parameters and accurate studies of phase equilibria. The presence of polar substances, those different from ethanol and water, and their low concentrations make it very difficult to model industrial distillation. Several of the congeners are essential enological components of the organoleptic matrix. In this work, we are concerned with the study of phase behaviour of ethanol + water + ethyl acetate at 101.3 kPa, this being the third compound, the legal congener of the highest composition in common alcoholic distillation. The experimental results showed partial miscibility and four azeotropes into a complex medium. Group contribution models yield poor results. Disposable literature was compared and commented upon. The lack of experimental data in multicomponent alcoholic distillation mixtures and the low reliability of the group contribution methods suggest a prudent application to process simulation.