A particle is disclosed. The particle comprising: (i) at least one inner core which comprises a solid matrix of nutrients for microorganism growth; (ii) an inner membrane being fabricated from a water-soluble polymer, the inner membrane surrounding the inner core and a population of dried microorganisms; and (iii) an outer porous membrane surrounding the inner membrane, the outer porous membrane being insoluble in water. Methods of generating same, propagating microorganisms within and uses of same are also disclosed.