Inhibitory effects of Sichuan pepper (Zanthoxylum bungeanum) and sanshoamide extract on heterocyclic amine formation in grilled ground beef patties

- The effects of Sichuan pepper and sanshoamide extract on formation of HAs were investigated.
- Sichuan pepper and sanshoamide extract has no effect on the nutritional and texture characteristics.
- Sichuan pepper and sanshoamide extract caused a decrease up to 100% in the amount of PhIP, IQx, MeIQx and 4,8-DiMeIQx.
- Correlations were observed between HA inhibition rates and pepper or sanshoamide extract levels.

This study evaluated the inhibitory effects of Sichuan pepper (Zanthoxylum bungeanum) and sanshoamide extract on the formation of heterocyclic amines (HAs) in grilled beef patties. The following major HAs were detected and quantified: imidazopyridine (2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine, PhIP), imidazoquinoxalines (2-amino-3-methyl-3H-imidazo[4,5-f]quinoxaline, IQx; 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline, MeIOx; 2-amino-3,4,8-trimethyl-3H-imidazo[4,5-f]quinoxaline, 4,8-DiMeIQx) and β-carbolines (9H-pyrido[3,4-b]indole, norharman; 1-methyl-9H-pyrido[3,4-b]indole, harman). The rates of PhIP, IQx, MeIQx and 4,8-DiMeIQx were inhibited significantly by 82%, 61%, 28% and 79%, respectively, in patties treated with a low-concentration of pepper (0.5%), and by 27%, 45%, 44% and 26%, respectively, following treatment with a low-concentration sanshoamide extract (0.005%). All inhibition rates exceeded 70% at pepper and sanshoamide extract concentrations of 1.0% and 0.010%, respectively. Harman and norharman could be significantly (p < 0.05) enhanced by the addition of all concentrations of Sichuan pepper, however, sanshoamide extract had no significant (p > 0.05) effect on them, although 0.005% of the extract could slightly increase the formation of them. Notably, significant correlations were observed between the HA inhibition rates and pepper or sanshoamide extract concentrations, especially for PhIP (r = 0.87, p = 2.30E−3), IQx (r = 0.99, p = 5.04E−7) and 4,8-DiMeIQx (r = 0.88, p = 1.96E−3). These results indicate that Sichuan pepper and sanshoamide extract could inhibit the formation of carcinogenic HAs during thermal preparation of protein-rich foods, and therefore might reduce the risk of chronic diseases associated with the long-term intake of HA-containing food products.