In a recent paper, Chu & Prosperetti (J. Fluid Mech., vol. 798, 2016, pp. 787-811) calculate the dissolution of a two-component droplet in an immiscible liquid. Here we discuss in what sense their results go much beyond the Epstein-Plesset solution of a dissolving single-component droplet and hitherto used approximations for dissolving multicomponent droplets. We also highlight the relevance of Chu & Prosperetti's result for liquid-liquid extraction processes for chemical analysis.