A fractionable polydisperse stable double oil-in-water emulsion, having 50 to 95 wt. % relative to the total weight of the double emulsion, droplets of an invert monodisperse emulsion Ei dispersed in a continuous aqueous phase. The continuous aqueous phase includes a polysaccharide thickening agent in a proportion of 1 to 10 wt. % relative to the total weight of the continuous aqueous phase, a water-soluble ethylene oxide and propylene oxide block copolymer as surfactant, and an osmotic pressure balancing agent. The emulsion Ei has a viscosity not higher than the viscosity of the continuous aqueous phase and has 50 to 95 wt. %, relative to the total weight of Ei, droplets of an internal aqueous phase dispersed in an oily phase. The internal aqueous phase includes an active hydrophilic substance and the oily phase includes poly glycerol polyricinoleate as surfactant.