Improving the Effects of Cold Saturated Salt Solution Immersion on the Texture of Black Rockfish (Sebastes schlegeli) Muscle

In the present study we investigated the physicochemical changes in black rockfish (Sebastes schlegeli) muscle subjected to immersion in a cold saturated salt solution and determined the optimal immersion conditions. Fish were sacrificed instantly by a spike to the head and immersed in cold saturated salt solution under various conditions. The onset of rigor mortis was accelerated by a decrease in immersion temperature and an increase in immersion time. Additionally, the time to reach full rigor was significantly shorter. However, the rigor index of samples of fish immersed in the cold saturated salt solution was decreased more than in samples of fish immediately after death. The breaking strength of the samples immersed in the cold brine solution increased slowly but did not increase under every set of conditions. The breaking strength of all samples immersed in the cold saturated salt solution decreased significantly after reaching the maximum value following immersion at -12.5[degrees]C for 5 mm. The ATP content was lowest under the aforementioned conditions (-12.5[degrees]C and 5 mm) and then increased. The lactate levels also increased under the optimal conditions and then decreased, in contrast to the ATP content. Transmission electron microscopy showed that the sarcoplasmic reticulum used in the treatment of black rockfish had natural triad stmctures between the Z lines, which were disrupted in samples immersed in the cold saturated salt solution.