A method to obtain gross blend morphological information from normal stress measurements is proposed. The blend consists of Newtonian and immiscible constituents in dilute conditions. It is shown that a master curve for the first normal stress difference (NI) can be readily obtained either theoretically or experimentally. The curve is parametric in the viscosity ratio, and relates the actual capillary number to the dimensionless interfacial stress. As a consequence, NI data determine a capillary number through which a characteristic dimension of the morphology can be estimated. Since globular morphology is typical in dilute conditions, as an example the master curve is here calculated by using a phenomenological model to describe single drop deformation. Morphology predictions are compared with experimental data found in the literature; the comparisons give satisfactory results even up to intermediate concentrations.