Change Of PAHs During Storage In Palm Oil And Palm Oil-containing Flavor Gravy

The potential risk of contamination of polycyclic aromatic hydrocarbons and oxygenated polycyclic aromatic hydrocarbons has aroused greater attention.Palm oil was widely used in food industry.This study measured changes of PAHs and OPAHs in palm oil and palm oil-containing flavor gravy during storage.We also determined the concentrations of PAHs in different palm oils,and dietary exposure and health risk were further evaluated.The main results are listed as follow:Firstly,we studied on the effects of light intensity on the concentration of 16 PAHs and 5 OPAHs in four palm oils during the storage time of 48weeks.Acid value,and peroxide value,increased with the storage time.After the storage time of 48 weeks,the total PAHs concentrations in four types of palm oil increased from 17.92–24.21?g/kg to 29.59–43.32?g/kg.The growth rate of total PAHs increased with the increasing light intensity,and reached up to 141.74%when the light intensity was 6000 lx.The concentration of light PAHs readily decreased during the storage,while the concentration of heavy PAHs tended to increased in palm oil.Secondly,the effects of storage temperature on PAHs and OPAHs in palm oil-containing flavor gravies were also measured.The concentration of PAHs and OPAHs increased with storage time,and the growth rate accelerated with the increasing storage temperature.The increase of total PAHs and OPAHs was not obvious when the storage temperature was 4°C and 25°C.Significant increase was observed when the storage temperature was 37°C and 45°C,with the concentration of PAHs and OPAHs increasing from 2.22–3.44 to 25.36–41.32 and from 0.67–2.46 to 18.34–20.06,respectively.Moreover,we chose four pairs of parent PAH and their corresponding OPAH,and analyzed their correlation during storage.The results showed that the correlation between these four pairs of PAHs/OPAHs got more significant with the increasing storage temperature.Finally,we used Monte Carlo simulation to estimate the dietary exposure and cancer risk from palm oil consumption.The dietary exposure and cancer risk were calculated based on benzo[a]pyrene equivalents.The results indicated that the concentrations of 16 PAHs in eight palm oils ranged from 2.12 to 60.53?g/kg.The concentrations of PAH4 five of eight palm oils didn't exceed the regulatory limit of 2.5?g/kg.The estimation of incremental lifetime cancer risks(ILCRs)indicated that the 95^th percentile with respect to PAHs exceeded the limitation of 10-6 for adults,especially in city.The results indicated that the potential carcinogenic risk should not be neglected.