21 C.F.R. § 172.876
Castor oil
The food additive castor oil may be safely used in accordance with the following conditions:
(a) The additive meets the specifications of the United States Pharmacopeia XX (1980).
(b) The additive is used or intended for use as follows:
Hard candy production—As a release agent and antisticking agent, not to exceed 500 parts per million in hard candy.
Vitamin and mineral tablets—As a component of protective coatings.