INFLUENCE OF ISOMERIZATION ON THE ABSORPTION OF CITRANAXANTHIN

In a typical formulation the feed additive citranaxanthin is usally pr esent as a mixture of several isomers. According to the degree of isom erization the UV/Vis-absorption of this pigment varies. In the present study the degree of isomerization of citranaxanthin was varied and th e respective absorbance was determined. The A(1)(1)-value increases in parallel with the content of the all-trans isomer. For a theoretical sample consisting of 100 % all-trans in cyclohexane, an A(1)(1)-value of 2680 was found by extrapolation. For a solution in acetone this val ue was 2700.