Heterocyclic amines in process flavours, process flavour ingredients, bouillon concentrates and a pan residue

Seven process flavours, five process flavour ingredients, four bouillon concentrates and a pan residue were analysed for mutagenic/carcinogenic heterocyclic amines. To improve chromatographic efficiency for samples with complex matrixes (process flavours, pan residues, etc.), a new additional purification method was designed. The following polar heterocyclic amines were detected: 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) in one sample (3.4 ng/g), 2-amino-3-methylimidazo[4,5-f]quinoxaline (IQx) in two samples (0.7–2.0 ng/g), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) in four samples (1.0–13.8 ng/g), 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline (4,8-DiMeIQx) in three samples (1.3–2.9 ng/g), 2-amino-3,7,8-trimethylimidazo[4,5-f]quinoxaline (7,8-DiMeIQx) in one sample (0.3 ng/g), and traces of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) in two samples. 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ) was not identified in any of the samples. The following non-polar heterocyclic amines were detected: 2-amino-9H-pyrido[2,3-b]indole (AαC) in one sample (0.4 ng/g), 2-amino-3-methyl-9H-pyrido[2,3-b]indole (MeAαC) in one sample (20.3 ng/g), 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1) in two samples (1.4–1.7 ng/g), and traces of 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2) in two samples. Of the co-mutagenic heterocyclic amines, 1-methyl-9H-pyrido[3,4-b]indole (harman) was identified in 15 of 17 samples (3.3–755 ng/g), and 9H-pyrido[3,4-b]indole (norharman) in 16 of 17 samples (1.2–176 ng/g). The polar heterocyclic amines were detected only in the samples of animal and mixed animal plus vegetable origin, while the non-polar heterocyclic amines were identified in samples of animal, mixed animal plus vegetable and pure vegetable origin.