Effects of oil types and pH on carcinogenic polycyclic aromatic hydrocarbons (PAHs) in grilled chicken

The effects of oil types and the pH of marinade were investigated on the formation of carcinogenic polycyclic aromatic hydrocarbons (EPA priority 16 PAHs) in grilled chicken. The formation of PAHs in grilled chicken breast with different marinades after charcoal-grilling for 3 min/side was evaluated using high performance liquid chromatography with a photodiode array detector (HPLC-DAD). Compared with the control marinade treatment (without vegetable oil), the addition of commercial palm oil and sunflower oil that contained significantly different amounts of polyunsaturated and saturated fatty acids led to a significant (p < 0.05) increase in the PAH levels in grilled chicken from 190.1 μg/kg to 457.6 μg/kg and 376.6 μg/kg, respectively and there was only a slight difference between both oil marinade treatments due to the presence of antioxidant compounds in the commercial vegetable oils. The pH values of the marinade treatments for both acidic and alkali marinades using citric acid and sodium bicarbonate, respectively, produced the highest pH value (7.51, alkali marinade) which resulted in a major increase of more than 70% in the PAH levels in grilled chicken. The results of this study suggested that the addition of oil and/or alkali ingredients in the marinade could be important in increasing the levels of PAHs in grilled meat products.     

Simultaneous analysis of 10 polycyclic aromatic hydrocarbons in roasted coffee by isotope dilution gas chromatography-mass spectrometry: Optimization,in-house method validation and application to an exploratory study

The presence of polycyclic aromatic hydrocarbons (PAHs) in food implies a potential risk to human health. Although the coffee has been appointed as an important matrix to be monitored for contamination by PAHs, there is still a gap in the literature regarding to the methods of analysis appropriately validated for this scope and also related to the occurrence of contamination in Brazilian commercial samples. In this paper, a method for the determination of ten priority PAHs in roasted coffee by isotope dilution gas chromatography coupled to mass spectrometry was optimized, validated and applied to an exploratory study with 24 commercial samples. The samples were extracted with simultaneous clean-up using pressurized liquid extraction (PLE), followed by liquid–liquid extraction (LLE) and clean-up using silica columns. Linearity was obtained in the concentration range from 0.25 to 4.00 μg kg⁻¹. Matrix effects were not significant. The precision was demonstrated with relative standard deviations varying from 3.3 to 24 % under repeatability and from 3.3 to 33 % under intermediate precision conditions. The average recovery values ranged between 87 and 111%. These values, as well as the limits of detection, limits of quantification and uncertainties of measurements, met the performance criteria established by European Union regulations. The contamination of the commercial samples ranged from 1.00 ± 0.35 to 11.29 ± 2.33 μg kg⁻¹, indicating the need of further occurrence studies and establishment of monitoring programs in Brazil.