Abstract:With fresh cod fish bladder as the subject of investigation，this study explored the effects of different freezing-thawing times on the physicochemical properties and quality of the cod fish bladder and analyzed the trends in changes of water retention capacity，color difference，textural characteristics，collagen content，total protein content，and microstructures of the cod fish bladder at different freezing-thawing times. The results showed that with the increase in the freezing-thawing times，the cooking swelling rate，brightness，hardness，elasticity，cohesion，adhesion，chewiness，and total protein content of the cod fish bladder decreased，with the amplitude of 29.65%，55.46%，57.94%，46.00%，16.88%，83.51%，69.36%，and 8.85%，respectively. Additionally，the collagen content decreased slightly，and the thawing loss rate and color redness value showed an upward trend by 12.61% and 596.59%，respectively. The microstructure of the cod fish bladder was gradually deconstructed and deteriorated during repeated freezing-thawing. Based on the rate of quality deterioration during freezing-thawing，the characteristics and quality value of the cod fish bladder could be effectively maintained in the case of no more than four freezing-thawing cycles.