Figure 2. The UV/vis spectra of retinol (red) measured at 10 ppm in methanol and retinyl palmitate (blue), measured at 10 ppm in tetrahydrofuran

The molecular structure and the two isomers of EHMC; both isomers are always present in some proportion and account for the two peaks in the HPLC chromatograms. determined by spectrophotometerc (see Figure 2).