In medium saucepan, combine sugar, gelatin and eggs; beat until smooth. Stir in milk; cook over medium heat until mixture coats a spoon, stirring constantly. DO NOT BOIL. Cool slightly.
Pour mixture into large blender container or food processor bowl with metal blade; blend at medium speed. While blender is running, add ice and spoonfuls of tangerine concentrate, blending until ice is melted. Pour into 1 1/2-quart bowl; refrigerate 10 to 15 minutes or until partially set.
Reserve 9 mandarin orange segments for garnish; place on paper towel. Fold remaining orange segments into mixture. Refrigerate 1 to 2 hours or until set. (If desired, mixture can be poured into individual dessert dishes before refrigerating).
Dip each orange segment halfway into melted chocolate; place on waxed paper. Let stand until set. Garnish each serving with chocolate-dipped orange segment.