Buyers look for the following indicators of good quality in fresh whole tuna:
• bright, clean appearance with little or no loss of original body colors;
• clear, moist eyes with black pupils;
• skin and scales unbroken;
• damage to the fish’s head by gaff is tolerated, but other mutilation or evidence of ulcers, parasitic
worm infestation, or physical injury lower the market value;
• moist, firm rigid skin elastic to the touch; and,
• abdominal walls smooth, clean and intact.
Proper care by the buyer or distributor involves grilling and gutting fish (if this has not been done at
sea) and repacking in ice for cold storage at temperatures of 28 to 32 degrees F. To avoid bleaching
of the flesh, loins, steaks or fillets produced from a whole tuna should be wrapped in plastic so that
there is no direct contact with ice or water.
Four species of billfish are caught in substantial quantities off the Hawaiian Islands:
• Pacific blue marlin (Makaira nigricans), kajiki or a‘u;
• Shortbill spearfish (Tetrapturus angustirostris) or hebi;
• Striped marlin (Tetrapturus audax), nairagi or ‘au;
• Broadbill swordfish (Xiphias gladius) or shutome.
With the exception of shutome, billfish are harvested in the open ocean by the same fleets which
land fresh tuna and they enter the same markets as tuna. Seasonality of species is evident, with
Pacific blue marlin most available during the summer months, striped marlin most available in the
spring and fall, and shortbill spearfish most available in the summer and fall. Shutome is predomi-
nant in spring and summer.
The same general procedures for proper care of tuna also apply to billfish. However, a handling
problem specific to billfish is their susceptibility to gaping or “cracking” if the fish is bent.
In a gutted billfish, buyers can determine freshness not only by examination of the exposed flesh,
but by squeezing the corner of the belly flap between thumb and forefinger. A rubbery texture indi-
cates freshness, but if the fingers penetrate the flesh, quality is lower. Another indicator of lower
quality in marlin is whether the small, finely-pointed scales break off or stick out after running a hand
across the skin. Gutted marlin, like gutted tuna, will keep better if the belly cavity is well iced. Loined
marlin should be bagged to protect the flesh from air and dehydration in cold storage. To extend the
shelf life of gutted marlin, the blood line should be completely removed. If oxygen from the blood
remains in contact with the flesh for a long time, the flesh may take on a somewhat rancid taste.
Blood denatures quickly, so removal of the blood line will also improve the life of fresh fillets.