The effect of ionising radiation on the colour of leg and breast of poultry meat

The effect of irradiation (0 and 5 kGy) of chicken, goose and turkey breast and leg muscles and subsequent storage at 4°C was studied in relation to colour changes. The colour of the outside surface was measured on the breast on each day of storage for up to 7 days post irradiation and for breast and leg and day 7. The colour of a freshly cut interior surface of both breast and leg was measured after 7 days storage. L* values of control and irradiated chicken, goose and turkey breast muscles changed little during storage post irradiation. The a* values for unirradiated goose breast were significantly higher than irradiated goose breast but declined to values similar to irradiated goose breast after 7 days of storage. The b* values for irradiated turkey breast were significantly higher than unirradiated turkey breast at all times post irradiation treatment. Analysis of variance was performed on the day 7 CIELAB values of breast muscle for the effects of species, surface and irradiation and their interactions. After 7 days storage a* values of poultry breast were higher on the freshly cut surface due to irradiation in all species, with decreases in hue angle due to irradiation. The a* values of leg of all species at 7 day post irradiation was significantly higher in the irradiated treatment than the controls. The results for the turkey leg indicate that this effect may be mainly due to higher a* values of the freshly cut surface. The possible role of carboxy form of the haem pigments as the irradiated pigment form is discussed.