A research note: Effect of natural antioxidants on color of an irradiated beef myoglobin model system

To determine the effect of antioxidants and irradiation on meat color, myoglobin (Mb) was extracted from beef hearts. Mb was treated with one of three antioxidants (control, grape seed extract, rosemary extract [RE] or oregano extract) and irradiated at 0.00, 1.25 or 2.50 kGy. The samples were then evaluated for pH, Commission Internationale de l'Eclairage L*, a* and b* values, hue angle, chroma and thiobarbituric reactive substances (TBARS). Antioxidants influenced pH. RE-containing beef Mb samples had lower pH values before and after irradiation. Antioxidants also had significant effects on the color of the beef Mb model system. RE-containing samples had the best pre- and postirradiated color in terms of a* value (redness) and chroma (color intensity). TBARS values were very low and did not differ regardless of antioxidant or irradiation dose.