EVALUATION OF MEAT QUALITY PARAMETERS IN DIFFERENT METHODS OF STUNNING NILE TILAPIA (Oreochromis niloticus).

The humane procedures of pre-slaughter and slaughter management aim to ensure the well-being of the animals from the time they are loaded on the property of origin until the moment of slaughter, avoiding unnecessary pain and suffering. In 2022, the Ministry of Agriculture launched a manual on the humane slaughter of fish suggesting some stunning techniques. The objective of this study was to compare the methods of pre-slaughter stunning of fish (hypothermia x electronarcosis x propofol) in Nile tilapia (Oreochromis niloticus) by monitoring the rigor mortis and pH determination. 18 tilapia between 300 and 800 grams were used, divided into three batches containing 6 animals each, the three batches corresponded to the groups worked: positive control (propofol), negative control (hypothermia) and electronarcosis. After the bleeding, rigor mortis was monitored every hour. During this time, samples of 10g of meat from the three groups were collected to perform pH determination in pH meter, previously calibrated in the microbiology laboratory measured in triplicate, for 72h at 24h intervals, starting at 0h, totaling 4 shots, in order to observe the pH changes during the rigor mortis process. When pH analysis, the electronarcosis group presented a mean of 6.34 at time 0, 6.48 at the end of 24 hours, 6.32 at 48 hours, and 6.47 at 72 hours; the hypothermia group had a mean score of 6.92 at time 0; 6.54 at the end of 24 hours; 6.28 with 48 hours, and 6.26 with 72 hours; while the propofol group had a mean of 7.37 at time 0; 6.61 at the end of 24 hours; 6.38 with 48 hours, and 6.21 with 72 hours