Abstract:The effects of temperature fluctuation amplitude on the quality of fresh meat and the phosphorylation of energy metabolism enzymes after slaughter were studied. The longissimus dorsi muscle samples of pork were assigned into three groups：control （4 ℃ constant temperature），fluctuation I （4 ℃ storage for 3 h→7 ℃ storage for 3 h→4 ℃ storage for 3 h），and fluctuation II （4 ℃ storage for 3 h→15 ℃ storage for 3 h→4 ℃ storage for 3 h）. The three groups were compared regarding the meat quality （pH value，cooking loss，and shear force），content of glycogen，ATP，and lactic acid，and activities and phosphorylation levels of glycogen phosphorylase（PYGM），aldolase A（ALDOA），and triosephosphate isomerase（TPI） during storage. The results showed that the fluctuation II group had higher pH 120 h after slaughter，higher cooking loss 72 h after slaughter，and higher shear force 72 h and 120 h after slaughter than the control group（P＜0.05）. The fluctuation II group had lower glycogen content 12 h after slaughter and higher lactate content 24 h after slaughter than the control group （P＜0.05）. The activities and phosphorylation levels of PYGM and TPI in the fluctuation II group were lower than those in the control group 24 h after slaughter （P＜0.05）. There was no significant difference in the activity or phosphorylation level of ALDOA among different groups（P＞0.05）. In conclusion，the increase in temperature fluctuation amplitude exacerbated the promoting effect of phosphorylation on PYGM activity and the inhibitory effect on TPI activity，accelerated energy metabolism after slaughter，promoted pH decrease，and reduced the water retention of fresh meat.