Changes in structure and color characteristics of irradiated chicken breasts as a function of dosage and storage time

Structural change and color characteristics of chicken breasts as a function of irradiation dose and subsequent storage process were investigated by visible spectroscopy and HunterLab measurement. Ratios of R1=A485 nm/A560 nm and R2=A635 nm/A560 nm, which are related to absorbances of the visible bands at 485 nm (metmyoglobin), 560 nm (oxymyoglobin), and 635 nm (sulfmyoglobin), suggested that relative amount of oxymyoglobin either increases as a result of irradiation, or decreases with the storage process. The plot of R1 and R2 versus storage time showed that the increments of both R1 and R2 are dose-dependent and that the relative amount of oxymyoglobin species in irradiated meats begins to decompose 7–12 days later than raw meats. In addition, R1 and R2 values were correlated with color index E∗ of chicken breasts.