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Fatty acid compositions and lipid contents of five common table species of marine fish from temperate Australian waters were determined for samples taken during two seasons (four species) and three locations of markedly differing latitude (one species). Variabilities in total lipid extract and phospholipid fatty acid compositions were assessed between samples of each species, as well as between individuals of the same sample. These were then compared with data obtained for the other species analysed. The highest n3 polyunsaturated fatty acid (PUFA) content lipids were found in fish from colder waters (southern locations and spring season catches). The leaner species were found to have much more stable lipid characteristics with changes in the water temperature at sampling.

Gamma-irradiation preservation of two species of Australian marine fish (Black Bream and Redfish) resulted in no significant changes in their fatty-acid compositions, even when performed at up to three times the commonly recommended maximum dose for fish. Vitamin E loss was evident in some fillets but could not be correlated with the treatment dosage. All irradiated fillets were found to have vitamin E contents above the levels believed to be desirable for human consumption, relative to the amounts of accompanying polyunsaturated fatty acids.

A method for the rapid identification of fish species by high performance liquid chromatographic (HPLC) analysis of water-soluble sarcoplasmic protein extracts is described. The method relies on the visual comparison of a star-symbol plot constructed from the sample's HPLC profile with those obtained from the mean profile data of morphologically identified species. A library of plots is presented for 15 common edible marine fish species from eastern Australian waters, but any suitable data can be used for star construction. The data presented are applicable to the identification of samples from any season or location, whether they are raw, gamma-irradiated, or dried with infra-red radiation. The procedure involves a single 10 min extraction followed by a 60 min analysis, without the use of an internal standard.