Abstract：The quality changes of Megalobrama amblycephalala were evaluated in terms of stiffness index, texture, pH, water-holding capacity, whiteness, and the contents of 5’-adenosine triphosphate (ATP) and related compounds during 72 h of postmortem storage at 4 ℃. At 6 h after slaughter, the hardness and stiffness index reached their peak, and then fell. The pH decreased rapidly after slaughter, decreasing to 6.58 ± 0.04 at 6 h, and then rose gradually. The water-holding capacity decreased firstly and then increased. The whiteness first rose and then fell to 38.02 ± 0.23 at 72 h. The ATP content was the highest at 2 h, and its trend was similar to that of 5’-adenosine monophosphate (AMP). The content of 5’-inosine monophosphate (IMP), produced from AMP degradation catalyzed by AMP deaminase, increased from 0 to 4 h. The content of hypoxanthine (Hx) increased significantly faster from 36 h onward. The K value was kept below 20% (the first freshness grade) up to 24 h after slaughter and remained within the range of 20%–40% (the second freshness grade) from 24 to 72 h.
2022, Vol. 36 
