Abstract: Providing a water slurry containing an immobilizing agent and an insoluble substance, such as calcium citrate, effective to cause gelation of the immobilizing agent. The water slurry is then contacted with a hydrophobic liquid, such as a vegetable oil under conditions leading to the formation of a dispersion of droplets of the water slurry in the hydrophobic liquid. The droplets gel to form microspheres by adding an oil-soluble organic acid, such as acetic acid to the dispersion containing the droplets. Possibility of producing microspheres which are very small and are constituted of nearly perfect spheres. If desired the method can be adapted to produce microspheres containing immobilized material.