HPLC-fluorescence analysis of polycyclic aromatic hydrocarbons (PAHs) in pork meat and its gravy fried without additives and in the presence of onion and garlic

The effect of onion and garlic on the formation of polycyclic aromatic hydrocarbons (PAHs) was evaluated by comparing the concentrations of PAHs in meat and gravy samples coming from pork dishes prepared in the presence and absence of these spices. PAHs were analysed by high performance liquid chromatography with fluorescence detection. The clean-up procedure included alkaline hydrolysis, solid-phase extraction (on columns with diatomaceous earth and propyl sulphonic acid) and column chromatography on silica gel. Total concentrations of 6 PAHs (benzo[b]fluoranthne, benzo[k]fluoranthne, benzo[a]anthracene, benzo[a]pyrene, dibenzo[a,h]anthracene, benzo[g,h,i]perylene) were (in ng g−1 of cooked meat) from 2.0 to 7.2 in meat samples and from 0.05 to 0.6 in gravies. Concentration of B[a]P was from 0.38 to 1.61 in meat and from 0.01 to 0.11 in gravy samples. Onion (30/100 g of meat) caused on average decrease of 60% of the total content of PAHs in pan fried meat and of over 90% in gravies. Garlic (15/100 g of meat) lowered the concentration of 54% in meat on average and from 13.5–79% in gravies.