S.C. Code Ann. § 39-31-30

The enrichment of rice or bulk rice may be accomplished by undermilling, treatment of the unhusked rice by such processes known as parboiling and conversion, addition of U. S. P. pure vitamins, addition of harmless and assimilable iron and calcium salts or by any combination of methods which produce enriched rice which meets the standards defined in this chapter. The use of harmless edible carriers and preservatives is permitted in only such amounts as needed for efficient marketing.