Core-shell nanofibers were prepared by electrospinning of corn oil-in-water emulsions stabilized by electrostatic gelatin-gum arabic complexes as a mixed monolayer. The addition of gum arabic decreased the apparent viscosity and induced a transition from a shear-thinning to a more Newtonian-like flow behavior of the emulsions, which helped form electrospun fibers with straight, bead-in-string, and spindle-like morphologies. These fibers had a high thermal decomposition stability upon heating to 250 degrees C, which was attributed to electrostatic interactions and newly formed hydrogen bonds between gelatin and gum arabic. The encapsulation efficiency of corn oil in fibrous mats at various mixing ratios was over 84%, and showed no significant changes during 7 days of storage. This work thus gives an insight into the development of electrospun nanofibers as encapsulation matrices using monolayer emulsions stabilized by electrostatic protein-polysaccharide complexes for applications in the food, pharmaceutical or personal care industries.