Scallop adductor muscle packed with an atmosphere of 100%O2, 80%O2 and 20%CO2, 60%O2 and 40%CO2, and air, and stored at 5℃. During storage, changes in the frequency of specimens rigor, total viable counts, and contents of ATP, its related compounds, octopine, L-arginine, and D-Lactic acid were examined. The growth of bacteria in the samples was inhibited in the atmosphere containing CO2 gas at the ratio of 20% or 40%. However the quality of scallop adductor muscle could not be preserved due to the rapid development of rigor. In the sample packed with 100%O2, it was remarkable that the decrease in ATP and pH, the development of rigor, the increase in octopine and moreover the increase in total viable counts was prolonged for nearly two days, compared with the sample packed with air.
From these results, it was elucidated that packaging with 100%O2 gas was a practical method and achived the prolongation for nearly two days in shelf life of the scallop adductor muscle.