Meat treated with Carbon Monixide can still be red 2 months after the expiration date. The gas is keeping the meat red. I have gone to the market and they have changed the labels with a new expiration date. And I have seen them slice through the ground beef that had a red new layer of meat covering the old meat.
The FDA approved the irradiation of meat. It kills mostly all dangerous bacteria and samonella in the meat. It will not make the meat radioactive. I am just about now ready to go vegetarian.