Abstract:

In the research, we compared the effectiveness of non-carbon monoxide treatments with L-histidine, niacinamide,
potassium nitrite and sodium nitrite for stabilizing the color of live tilapia and tilapia fillets. Potassium nitrite was found to
be the color stabilizer of choice for tilapia fillets. We further analyzed the influence of potassium nitrite dosage, treatment
time, fish-to-water ratio, farming water temperature and bloodletting methods on the color of tilapia and optimized these
factors. The results showed that potassium nitrite concentration, treatment time and fish-to-water ratio all had significant
effects on the color of tilapia fillets, and their optimal levels were determined by orthogonal array design to be 1.5 g/kg, 2 h
and 1:10, respectively. Under these optimal conditions, the L*, a* and b* values of tilapia fillets were 45.03, 7.42 and 13.18,
respectively, and the sensory score was 4.4. In addition, the nitrite residue in tilapia fillets did not exceed 10 mg/kg, which
was in accordance with the Chinese national standard GB 2760?2011: Standards For Uses of Food Additives.

Key words: tilapia fillets, color fixative, color, potassium nitrite, sensory evaluation