St Jeans process yields about 45% loin meat out of a frozen tuna. They partially thaw out the tuna in a cold water solution then loin them, chamber seal them and refreeze.you get about 40% meat out of a whole tuna right? If I could confidently get good quality loins all packed up I'd be happy to pay that price. Last year I think I got about 16 lbs of loins out of two 20 lb tuna. Paid $120 for the fish and had to do all the work myself.
I find it hard at home to figure out how to thaw out properly so you can skin the tuna then loin them before they get too soft.