Cut papayas in half lenghtwise, scoop out and discard seeds. Scoop out 4 small balls with a melon baller, reserve for garnish.
Carefully scoop out remaining pulp, reserve papaya shells.
Puree papaya with lemon juice and sugar in a blender until smooth. Beat cream until stiff. Quickly, but gently fold papaya into cream (do not over mix). Pour mixture in a container. Freeze for 1 hour or until frozen 1-inch around edge. Stir with spoon when serving.
