Ask the dietitian: Two-toned ground beef is probably fine  Dear
Vicky: Every so often, the ground beef I buy is two-toned — pink
on the outside and more grey in the middle. Is this anything I
should be concerned about? — B.R., Hudsonville  A: According to
the June 2010 issue of the University of California, Berkeley
Wellness Letter, your ground beef is probably fine.  A natural
pigment in meat, myoglobin, turns red when exposed to oxygen.
The plastic overwrap allows a little oxygen to get through, so
the surface of the ground beef appears red. The ground beef in
the middle is not exposed to oxygen when it is packaged, and the
myoglobin turns grayish brown.  If the ground meat is gray-brown
throughout, it may indicate the meat is beginning to spoil.
Salmonella and E. coli are bacteria that may be found in ground
beef and can make you sick. Neither of these bacteria change the
color or odor in meat, so you can’t tell from a glance or sniff
if the ground beef is contaminated. Use or freeze ground beef
within a