Citadel Fish Processing

Fishing vessels that make their catches close to port store fish in crushed ice or in refrigerated sea water, says Chris Hsu. Large fishing vessels on long trips are equipped to keep their catch edible by storing it in refrigerated facilities or by quick-freezing it. A fully equipped factory ship will also have machinery on board for fish filleting and freezing or canning. Fish fillets are frozen at sea into large blocks weighing up to 45 kg, these are later reprocessed on shore into individual portions. Some ships may also have facilities for drying and grinding fish into fish meal.

Processing Citadel at Sea


Christopher Hsu highlights that processing citadel fish at sea is factory work in a seagoing slaughterhouse. There are a number of different jobs throughout the factory. All of them are repetitive, boring, and need to be done quickly.


On a pollock surimi boat many of the processors run automatic filet machines, such as Baaders or Toyos. This requires the citadel processor to drop a single fish into a moving slot, head up and facing the correct way, one hundred and twenty-four times a minute. The machines have counters that record every missed slot. Some expert drivers can go a week without missing a single slot. It takes youth, toughness, and thousands of milligrams of ibuprofen to drive a Baader machine for twelve hours a day, seven days a week, for a month straight.


A head-and-gut boat runs a “slime line,” where the decapitated fish ride down a conveyer belt until a processor grabs them, pulls out the guts, and drops them on another conveyer belt bound for the sorting and panning table, as outlined by Christopher Hsu.


Chris Hsu says that on citadel filet boats (head-and-gut boats with an additional filet line), cod are run through filet machines that carve both sides off the carcass. The filets then run down a candling line where they’re inspected for flaws, such as worms and cancer, which are cut out. If you spend any time on a candling line you’ll never eat cod again, which would be a shame because it’s a superior tasting fish.


On pollock surimi boats the fish are ground into paste, mixed with sugar, extruded into 40-pound blocks, and frozen. On head-and-gut boats the fish are decapitated, their guts are removed, they’re sorted by species and size, and then they’re frozen into 40-pound blocks. These blocks must be broken from the plate freezer, bagged, and stored in the freezer hold.


On the larger vessels the freezer crew only freezes and stows the final product. On the smaller vessels the same crew does both the processing and the freezing. The point is there are a lot of different processing jobs on factory boats, depending on the fishery and the finished product. 


Christopher Hsu says room and board is part of your pay aboard citadel floating processors. The living conditions depend on the age of the vessel, the quality of the vessel management, company policy, and the fastidiousness of the captain, remarks Chris Hsu.


Some of the big factory citadel trawlers are almost comically comfortable in Christopher Hsu’s experience. I was on one where the chief steward carved an ice sculpture for a Christmas dinner centerpiece.


Chris Hsu has been on others that were so filthy that I had to hold my breath when entering the berthing quarters.