TDK conference 2018

Knowing what kind of undesirable substances are transferred into our body with consumed food becomes more and more important. These harmful substances can get not only by exogenous way into our food, but may also be formed during processing. Such a potentially carcinogenic group of compounds formed during heat treatment are the heterocyclic amines (HCAs), first described by Sugimura et al in 1977, in heat-treated fish and meats over 150oC. HCAs can be divided into two groups based on their formation and structure: aminoimidazoarenes (thermic amines) and aminocarbalines (pyrolitic amines). Members of the former group are formed during the Maillard reaction at a temperature of 150-300 oC in the presence of creatine, reducing sugars and free amino acids, while the aminocarbalines are formed mainly over 300 oC by proteinpyrolysis.

My experiments were aimed at determining the amount and nature of the carcinogenic organic substances produced in grilled chicken meat, prepared by modeling the domestic kitchen circumstances. We examined the most representative HCAs from both types to poultry according to the literature.

During the tests we baked chicken breast pieces of 1 cm width on a contact grill under continuous core temperature monitoring. We examined six control groups, the two test variables were the baking time (5 and 10 minutes per side) and temperature of the grilling surface (3 temperature grades). We also measured the baking loss compared to the initial weight, as well as, the color of meat resulting after baking. The HCA content of meat samples was investigated by LC- MS/MS measurements following a suitable sample preparation procedure.

Based on our results it can be stated that the baking temperature and time are related to the amount of carcinogenic HCAs formed. In the meat grilled for 10 minutes carcinogenic MeIQx was detected even when grilled at grade 1 (85 oC), which was surprising at this temperature according to the literature results. On grade 5 (240 oC) the amount of produced HCAs increased significantly in all examined compound groups. The amount of produced HCAs during 10 minutes baking was an order of magnitude higher compared to the 5 minute group. For example one of the aminoimidazoarenes, PhIP appeared in 7,97 ng/mg and 0,58 ng/mg concentrations in the longer and medium period grilled meat, respectively. It can be concluded from these results that the temperature terms and time factor of heating process are very important to the formation of HCAs.