Paper Title
Influence of Light and Temperature on Lipid Oxidation and Colour Changes of Corn Oil Including Curcumin

In order to introduce a natural antioxidant for food industry, the active substance of turmeric rhizome (curcumin) was extracted and identified with thin layer chromatography (TLC) and nuclear magnetic resonance (NMR). To evaluate the lipid oxidation and colour changes of corn oil samples, including different concentrations of curcumin (0.02%, 0.04% and 0.08%) stored at 25˚C and 45˚C in lightness and darkness, the Iodine value (IV), acid value (AV) and L* a* b* values for colour changes during 90 days monitored. The result of TLC analysis and NMR spectra corroborated the chemical structure of curcumin. Results from IV and AV showed that increasing curcumin concentration leads to decreasing the oxidation rate significantly. The results from the colour changes of the samples showed the total colour change (ΔE) in darkness and lightness was thoroughly different. But temperature had not any significant effect. Keywords: Acid value, Colour changes, Corn oil, Curcumin, Iodine value, Natural antioxidant