Hi. Hwang et Lb. Hau, EFFECTS OF IONIZING-RADIATION ON THE ENZYME-ACTIVITIES AND ULTRASTRUCTURAL-CHANGES OF POULTRY, Radiation physics and chemistry, 46(4-6), 1995, pp. 713-716
Citations number
12
Categorie Soggetti
Nuclear Sciences & Tecnology","Chemistry Physical","Physics, Atomic, Molecular & Chemical
Enzyme-catalyzed changes are generally recognized as one of the major
reasons for fresh meat deterioration after irradiation. In this study,
the effects of ionizing radiation and storage on the enzyme activitie
s of poultry as well as the ultrastructural change of muscle were eval
uated. When chicken breasts were irradiated at 4 degrees C and -20 deg
rees C, both Ca2+-dependent protease and cathepsin D showed some degre
e of resistance to irradiation. The activities of those two enzymes de
creased with the increase of irradiation doses. During storage, Ca2+-d
ependent proteases showed a marked decrease in activity. On the other
hand, the cathepsin D activity was not significantly changed at either
4 degrees C or -20 degrees C after 20 days. Transmission electron mic
roscope examination showed no structural changes of the myofibrils wit
h a radiation dose of up to 10 kGy at either 4 degrees C or -20 degree
s C. Freezing protected the irradiated chicken breasts from autolytic
enzymes damage during storage. In contrast, considerable sarcomere deg
radation occurred in Z-line for irradiated samples when stored at 4 de
grees C for 20 days. The action of the proteolytic enzymes may have be
en responsible for the sarcomere degradation in irradiated chicken bre
asts.