Discoloration Mechanisms in Vacuum-Packaged Beef

This narrative review aims to provide a comprehensive overview of meat color in vacuum-packaged beef, focusing on intrinsic and extrinsic discoloration mechanisms throughout the whole beef production process. The review describes fundamental knowledge about wet-aging, vacuum-packaging, meat color, consumer acceptance, and postmortem metabolism. It also explains the intrinsic discoloration mechanisms, involving various chemical and biochemical oxidizing processes of myoglobin. These mechanisms are also influenced by muscle type and composition. Further, extrinsic discoloration mechanisms. These mechanisms include microbiology, slaughtering, vacuum packaging and its application, and storage. This review summarizes all fundamentals necessary to understand the biochemistry of meat color and provides a comprehensive overview of possible discoloration mechanisms and causes in beef. The knowledge acquired is applied to the vacuum-packaged beef production chain and offers valuable insights for developing effective prevention strategies. Important findings are that the extrinsic factors are currently easier to influence than intrinsic factors. There are knowledge gaps in relation to discoloration and mitochondrial metabolism, reducing systems of meat, and oxygen concentration in packaging. Also, the influence of the microbiome on discoloration and postmortem metabolism of the meat and the influence of the living conditions and feed on color-stabilizing intrinsic factors of the meat should be further investigated.