The sensory analysis was conducted by a sensory panel of five experienced judges, three male and two female with an age in the 25-50 yr range, according to the guidelines concerning fresh and refrigerated fish compiled in Table 1 (Council Regulation,1990). The panellists had been involved in sensory analysis of different kinds of fish and seafood products for the last ten years. Before the present experiment, a special training was administered on chilled hake, megrim and angler. Such training consisted in the evaluation of refrigerated specimens belonging to the three species and exhibiting different initial qualities. Special attention was paid to the evolution of the different sensory parameters for each species from the initial state until the sensory attributes were not acceptable.
Four categories were used to rank the samples: highest quality (E), good quality (A), fair quality (B) and unacceptable quality (C). Sensory assessment of the fish included the following parameters: gills (odour, colour and mucus development), eyes, external odour (development of putrid and other off-odour), muscle odour (raw and cooked fish; development of putrid and other off-odour) and taste (cooked fish; development of putrid and other off-taste). At each sampling time, whole fish specimens were presented to the panellists in individual trays, which were scored individually.