Carbon dioxide and fresh meat

Will Carbon Monoxide Cause You to Buy Spoiled Meat? Some meat is packaged in an atmosphere high in carbon monoxide, as opposed to normal air. The carbon monoxide binds to the myoglobin (a protein) in the meat to cause it to look the pink color most of us associate with fresh meat. The chemical reaction that causes the color fixation doesn't present a health hazard, but there are concerns about consumer safety because people buy meat according to how it looks. Meat that has been packaged in a carbon monoxide-rich atmosphere will continue to look pink past the point when it should be sold. Untreated meat gets darker in color as it stays on the shelf. Of course, there are other indicators of freshness. A slimy appearance is a giveaway of decay, as is bulging packaging from the gases produced by bacteria. If you could smell the meat, you'd know whether or not it's good, too.