Effects of deep seawater acclimation on components and texture of the muscle of red sea bream

To examine the effect of deep seawater (DSW) acclimation on properties of t he fish muscle, we reared red sea bream Pagrus major in DSW, surface seawat er (SSW) and chilled surface seawater (CSSW) which was chilled to the same temperature as DSW. Free amino acid (FAA) content, total lipid content, fat ty acid (FA) components of lipid, and texture of the ordinary muscle were c ompared 30 and 87 days after the start of rearing. It was found that acclim ation to DSW and CSSW induces an increase of Gly, Lys and His in FAA. The p roportion of docosahexaenoic acid (DHA) in FA was stable in fish reared in DSW and CSSW while it decreased in fish reaed in SSW. In addition, an incre ase of hardness of the muscle after the acclimation to DSW and CSSW was det ected by texture analysis. Such changes were not significant after rearing for 30 days and became remarkable after rearing for 87 days. Since such cha nges in FAA, FA, and texture were observed both in DSW and CSSW groups, the y were presumed to be caused mainly by the low temperature of DSW.