Effect of Gallic Acid on the Inhibition of 2-Amino-3,8-Dimethylimi-Dazo[4,5-f]Quinoxaline in Fried Tilapia.

Tilapia produces the potentially carcinogenic toxic substance 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) when fried at high temperatures. Therefore, this study investigated the effects of different concentrations of gallic acid (GA, 0.03%, 0.06%, and 0.09%) on the formation and inhibition pathways of MeIQx in tilapia fried for 4, 6, and 8 min. The results showed that GA inhibited MeIQx formation in fried tilapia across all frying durations (65.43-83.11%). Additionally, GA increased the content of glucose and creatine, precursors of MeIQx, while decreasing the content of threonine, glycine, and creatinine. GA promoted the generation of formaldehyde and acetaldehyde while reducing glyoxal and methylglyoxal content. Principal component analysis indicated that MeIQx was associated with creatine, creatinine, glyoxal, and methylglyoxal, exhibited positive correlation with creatinine, glyoxal, and methylglyoxal, and negative correlation with creatine. GA increased creatine content and reduced the levels of creatinine, glyoxal, and methylglyoxal. In conclusion, GA may inhibit MeIQx formation in fried tilapia by inhibiting the conversion of creatine to creatinine and scavenging glyoxal and methylglyoxal. PRACTICAL APPLICATION: Gallic acid, as a natural antioxidant, can reduce the formation of the harmful substance MeIQx in fried tilapia during a high-temperature process. These findings from this study provide theoretical support and valuable insights into the impact of GA on MeIQx generation in fried tilapia, offering a promising approach for controlling MeIQx in high-temperature processes.