Irradiation significantly decreased the redness of ground
beef, and the visible color of beef changed from a bright red
to a green/brown depending on the age of meat. Addition of
ascorbic acid prevented color changes in irradiated beef, and
the effect of ascorbic acid became greater as the age of meat
or storage time after irradiation increased. The ground beef
added with ascorbic acid had significantly lower ORP than
control, and the low ORP of meat helped maintaining the
heme pigments in reduced form. During the aerobic storage,
the S-volatiles disappeared while volatile aldehydes
significantly increased in irradiated beef. Addition of
ascorbic acid at 0.1% or sesamol + α-tocopherol at each
0.01% level to ground beef prior to irradiation were
effective in reducing lipid oxidation and S-volatiles. As
storage time increased, however, the antioxidant effect of
sesamol + tocopherol in irradiated ground beef was superior
to that of ascorbic acid.