Heterocyclic amines in several types of cooked meat and chicken dishes which form part of the Korean diet

Abstract

Heterocyclic amines (HAs) are formed in protein-rich foods during high temperature cooking such as frying and grilling. The amount of HAs formed in several of the most frequently eaten food dishes in Korea such as Bulgogi (roasted beef), Galbi (grilled rib of beef), Samgyupsal (grilled boned rib of pork), fried chicken, charcoal grilled chicken and electrically grilled chicken, was determined. The ground-up samples were extracted under both acidic and basic conditions, cleaned on SPE cartridges, and the concentrations of fifteen HAs determined using electrospray ionization LC/MS. Limits of detection (LODs) and quantification (LOQs) were 0.99 ng g-1, and 3.33 ng g -1 for both MeIQ and Trp-P-1, and 0.51 ng g-1 and 1.67 ng g-1 for the remaining HAs. The absolute recoveries of the raw meat samples at a concentration of 3.33 ng g-1 (n=3) ranged between 60 and 100% for most of the HAs. The precision of inter-day assays was 1.0-15.3%. The range of inaccuracy for inter-day assays was -18.2 to 18.3% (bias) at a concentration of 25 ng g-1. Norharman, Harman, MeAaC and MeIQx were the amines the most frequently found in the cooked dishes, with concentration ranges of 17.4 - 261.0, 21.6 - 267, 3.61 - 27.7, and 6.45 - 20.8 ng g-1 respectively. While PhIP was the most frequently found HAs in the cooked pork (Samgyupsal) (5.2 - 17.2 ng g-1) and chicken breast (9.3 - 66.1 ng g-1), being present at high concentrations, it was detected in only one of the ten samples of cooked beef. Trp-P-2 was found in a few of the foods and its concentration was less than 5 ng g-1. In the investigation of the HAs contents according to the cooking method for the chicken breast, the highest amounts and frequencies of HAs, were found in the electrically grilled chicken breast, with 4,8-Di-MeIQx, 7,8-DiMeIQx and AαC being especially abundant. Since Bulgogi, Galbi, Samgyupsal and cooked chicken breast are the most popular meals among Korean people, regular consumption of such items may contribute substantially to their dietary intake of HAs.