Credit: Gabriel Salvo Parra (Chile) Description: Abdel Rahman El Gamal
The swimming nature of tunas influences the color and flavor of tuna meat. The red coloration derives from the oxygen-binding muscle pigment “myoglobin” which is expressed in tunas in quantities far higher than most other fish species. When the fish is cut up and the oxygen comes into contact and absorbed into the myoglobin in the exposed tuna meat surface, the attractive bright red or pink pigment develops in tuna meat. As the storage of tuna meat continues in the display case, and as a result of oxidation due to the more exposure to oxygen, the red color of tuna meat darkens and gradually changes into brown color due to the brown pigment “metmyoglobin” indicating – to consumers- less freshness of displayed tunas. The bluefin tuna has been named in Spanish after its red meat as “atún rojo”.
The meaty flavor of tunas comes from the mass of muscles that tunas develops during its constant swimming trying to get water high in oxygen, which is necessary for tuna.
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