Seasonal variations in dorsal muscle constituents of wild black sea bream Acanthopagrus schlegelii in Hiroshima Bay, Western Japan

To obtain basic information on carcass quality and nutritional condition of wild black sea bream Acanthopagrus schlegelii in Hiroshima Bay, we analyzed monthly and seasonal changes in major quality parameters, such as proximate composition, free amino acid, fatty acid, and stable isotope in dorsal muscle. Lipid content indicated a significantly seasonal variation with minimum value at 0.2% in March and maximum value at 0.6% in October while the average value was relatively low at 0.34%. Alanine, glycine and glutamine which are related with taste and sweetness, namely “umami taste,” were deposited from autumn to early spring. Therefore, these several amino acids could have a favorable effect on fillet taste. Overall, δ13C and δ15N in dorsal muscle of omnivorous black sea bream were noted at −15.9‰ and 16.6‰, respectively. The fluctuation in δ15N, taurine and HUFA in dorsal muscle also may reflect seasonal changes in foods composition and/or feeding activity of wild black sea bream in the Bay.