Effects of Various Agents on Colour Tests for Vitamin A

Abstract

Fearon''s "pyrogallol" test is non-specific for vitamin A. Concentrated H2SO4 and P2O6 are less sensitive tests for vitamin A than ASCI3 or SbCl3, which indicate parallel results in vitamin A destruction in cod liver oil by ultraviolet light. AsCl3 is the most sensitive of the vitamin A color reagents, but readings should be made within 30 sec. after mixing because of the transient nature of the colors.