Abstract
Changes of impedance at 2 kHz, muscle contraction and ATP content in cultured yellowtail were measured during 0 (ice), 5, 10,
15, 20 °C storage, and histological changes were analyzed by light microscope during ice storage. The relative impedance at each
temperature increased during early storage and then deceased, while each muscular contractile percentage increased with ATP
consumption. The increasing speed of relative impedance was synchronous with the increasing speed of muscle contraction at any
storage temperatures, and their increasing speeds were followed by 0°C ≒ 20°C > 5°C > 10°C > 15°C. In addition, the narrowed
and expanded intercellular spaces were respectively observed at 4 h and at 20 h, which were accompanied by the development of
muscle contraction and impedance. These results suggest that the temporal rise in impedance during early storage has a significant
relationship with rigor mortis and narrowing of intercellular space.
