Bones are occasionally present in canned tuna, although every effort is made to remove them. Highly trained personnel trim the loins entirely by hand. After this process, the loins are inspected several times for the presence of bones that may have been missed. On occasion, however, a bone is embedded in the loin and may be overlooked. The high heat sterilization process, after the fish has been canned, will normally soften them to the point where they will easily crumble.