Impact of Precursors Creatine, Creatinine, and Glucose on the Formation of Heterocyclic Aromatic Amines in Grilled Patties of Various Animal Species

Abstract

The impact of precursors such as creatine, creatinine, and glucose on the formation of mutagenic/carcinogenic heterocyclic amines (HAs) were studied in patties of 9 different animal species equally heat treated with a double-plate contact grill. All grilled patties of the various species (veal, beef, pork, lamb, horse, venison, turkey, chicken, ostrich) contained several HAs such as MeIQx (2-amino-3,8-dimethylimidazo[4,5-f] quinoxaline; 0.5-1.4 ng/g), 4,8-DiMeIQx (2-amino-3,4,8-trimethylimidazo[4,5-f] quinoxaline, 0 to 1.3 ng/g), PhIP (2-amino-1-methyl-6-phenylimidazo[4,5-b] pyridine, 1.2 to 10.5 ng/g), harman (1-methyl-9H-pyrido[3,4-b] indole; 0.5 to 3.2 ng/g), and/or norharman (9H-pyrido[3,4-b]indole 0.5 to 1.9 ng/g). Residual glycogen (glucose) content varied greatly from 0.07 to 1.46 wt% on a dry matter (DM) basis. Total creatin(in)e content in raw meat (1.36 to 2.0 wt% DM) hardly differed between species, except in turkey and ostrich (1.1 wt% DM). Chicken contained, compared to all other species, very low concentrations of glucose (0.07 wt% DM) and the highest levels of nonprotein nitrogen compounds. The free amino acids lysine (r = 0.77, P < 0.001), tyrosine, phenylalanine, proline, isoleucine, and aspartic acid (r = 0.47-0.56, P < 0.05) showed significant correlation to PhIP in chicken. Also a linear correlation was found to exist between PhIP (r = 0.87, P < 0.001) and MeIQx (r = 0.35, P < 0.01), and the molar ratio of creatin(in)e to glucose, respectively. Harman as co-mutagens was linearly correlated to the concentration of glucose (r = 0.65, P < 0.001). By contrast, norharman was not significant correlated to glucose levels.