Although ono is used as a substitute for mahimahi, mahimahi is more moist and sweeter than ono. When the fish is headed and gutted, the collar bone and belly areas are exposed to bacteria which can then cause accelerated deterioration of the remaining flesh. The first external evidence of deterioration in a whole ono is discoloration of the skin around the head and gill plates and a general softening of the flesh. In a dressed fish, discoloration of the flesh exposed around the collarbone would indicate a loss of quality. Poor quality fillets have opaque, milky flesh or they may be cracked.
Local fishermen market their ono as fresh, whole fish.
Most is purchased by up-scale restaurants in Hawaii and on the mainland. Some restaurants buy fillets from intermediary suppliers, but others prefer to receive the fish headed and gutted to retain better quality. Although one of the best fish for smoking, ono is too expensive to be put to this use in Hawaii. Ono flesh is whiter, flakier, and has a more delicate texture than the meat of other fast-swimming, pelagic species. One way to retain moisture in a lean fish is to poach.