While using canned tuna to make salad, I remembered a Youtube video about sushi-grade tuna. If I recall correctly, the main criterion was if it contains parasites and that it's rather hard to find a clean fish, which makes them so highly priced. Especially the tail was heavily infested when they sliced up an example.
Now, since I have nothing better to do while eating, I thought I could ask how likely it is, that I'm currently eating some cooked tuna parasites?
Best Answer
It is quite likely that it does contain them, yes.
A randomly chosen nonpaywalled study of Mediterannean tuna (DOI: 10.14411/fp.2014.011) says that
Now these are the gills, not the meat in the tin, but it is unlikely that there will be much information on the meat itself:
I don't know enough about fish parasite to tell you whether the 11 species found are all gill-only, but that sounds unlikely. Where there is an ecological niche, it will be filled. So, extrapolating from the gill parasite numbers to body parasite numbers doesn't sound too bad. And I am pretty certain that the people who prepare the fish don't have any method or reason to go remove the parasites from within the fish meat, just like apple sellers don't have a method to remove the worms from apples. So it sounds entirely believable that there are parasites in most cans of tuna, and if you eat enough of them, your chance of never eating a cooked parasite goes against zero.