Effect of chemical modification of κ-carrageenan on its inhibitory effect against heterocyclic amine (HAs) formation in roasted tilapia fish patties.

Sulfated κ-carrageenan (S-KC), carboxymethylated κ-carrageenan (C-KC), acetylated κ-carrageenan (A-KC) and phosphorylated κ-carrageenan (P-KC) were synthesized and tested for their inhibitory effect on heterocyclic amine (HAs) formation in roasted tilapia fish patties. Fish patties with 1 % of each hydrocolloid prepared by 90 % of fish and 10 % of an aqueous hydrocolloid dispersion were determined for HAs-levels after roasting. P-KC showed the strongest inhibitory effect against total HAs formation (20.95 %). Moreover, P-KC increased the content of creatinine and glucose but decreased the content of free amino acids in fish patties, indicating that P-KC may compete with creatinine and glucose to react with amino acids to suppress HAs generation. In addition, P-KC plus naringenin had a stronger inhibitory effect against HAs formation than P-KC or naringenin alone. P-KC at 1 % (w/w) and P-KC (0.5 %, w/w) plus naringenin (0.5 %, w/w) showed no significant effects on the color and textural properties compared to the control group (100 % fish), and had less impact on food quality than 1 % (w/w) KC. Therefore, our results suggest that chemical modification could enhance the inhibitory effect of some hydrocolloids on HAs formation, and an appropriate combination of hydrocolloids and flavonoids contributes to the attenuation of dietary exposure to genotoxic HAs.