Study on the Stability of Carotenoid Pigments

The effect of light, heat, acids, oxidant and reducing agent on the stability of carotenoids from Rhodotorula were studied, The results showed that the carotenoids from Rhodotorula are sensitive to heat, light, acid and oxidant. The absorbance at 475nm of carotenoids was weakened with the raise of temperature. Carotenoids was unstable under light especially outdoor sunlight. Carotenoids were also unstable under ultraviolet and indoor scattering. The absorbance at 475nm of carotenoids is almost no change in light-free condition. It has been found that the carotenoids from Rhodotorula were unstable under acidic condition. Oxidant (hydrogen peroxide) can also oxidized the carotenoids from Rhodotorula. However, Reducing agent (Vc) has protective effect on the carotenoids from Rhodotorula.