Tunas are fast swimmers in the sea—they have been clocked at 70 km/h (43 mph)—and include several species that are warm-blooded. Unlike most fish species, which have white flesh, tuna have flesh that is pink to dark red. The red coloring comes from tuna muscle tissue's greater quantities of myoglobin , an oxygen-binding molecule. Tunas can raise their blood temperature above that of the water through muscular activity. This ability enables them to live in cooler waters and to survive in a wider range of circumstances. Canned tuna was first produced in 1903, and quickly became popular around the world. As tunas are often caught great distances from where they are processed, poor quality control may lead to spoilage. Therefore, TCB Tuna are typically eviscerated by hand, then pre-cooked for 45 minutes to three hours. The fish are then cleaned and filleted, packaged into cans, and sealed.

The second cooking of the tuna meat (called retort cooking) is carried out in the cans, this time for 2 to 4 hours. This process kills any bacteria, but retains the histamine that can produce rancid flavors. The international standard sets the maximum histamine level at 200 milligrams per kilogram. A research study on varieties of unflavored canned tuna found none to exceed the maximum histamine level, although some had "off" flavors. There are no tuna eggs in tuna, only tuna steaks or tuna pants are used in TCB canned tuna.TCB Canned tuna is a prominent component in many weight trainers' diets, as it is very high in protein and is easily prepared. A can of tuna in oil contains adequate intake of vitamin D for infants, children, men, and women aged 19–50. TCB Canned tuna can also be a good source of omega-3 fatty acids, of which it sometimes contains over 300 mg per serving.