Can you eat meat once it has turned grey?

No, you should discard and not consume meat that has turned grey. When meat is exposed to air, its myoglobin starts to oxidise and react with oxygen, resulting in a change in colour. Grey meat signifies decomposition, bacterial growth, and deterioration, making it unsafe for consumption. Fresh meat is usually bright red or pink in colour. Meat that has gone through the oxidation process tends to be harder, drier, and has an off-putting smell.