The loss and fate of BaA, Chr, BbF, and BaP (PAH4) tracked by stable isotope during frying

Recent Advances in Sample Preparation and Chromatographic/Mass Spectrometric Techniques for Detecting Polycyclic Aromatic Hydrocarbons in Edible Oils: 2010 to Present

Polycyclic aromatic hydrocarbons are considered to be potentially genotoxic and carcinogenic to humans. For non-smoking populations, food is the main source of polycyclic aromatic hydrocarbons exposure. Due to their lipophilic nature, oils and fats rank among the food items with the highest polycyclic aromatic hydrocarbon content. Consequently, the detection of polycyclic aromatic hydrocarbons in edible oils is critical for the promotion of human health. This paper reviews sample pretreatment methods, such as liquid-phase-based extraction methods, adsorbent-based extraction methods, and the QuEChERS (quick, easy, cheap, effective, rugged, and safe) method, combined with detection techniques like mass spectrometry and chromatography-based techniques for accurate quantification of polycyclic aromatic hydrocarbons in edible oils since 2010. An overview on the advances of the methods discussed herein, along with a commentary addition of current challenges and prospects, will guide researchers to focus on developing more effective detection methods and control measures to reduce the potential risks and hazards posed by polycyclic aromatic hydrocarbons.

Halogenated polycyclic aromatic hydrocarbons in Chinese traditional sausages with high salt: Profiles in market samples and formation during home cooking

Halogenated polycyclic aromatic hydrocarbons (XPAHs) are likely to be generated by the reaction between polycyclic aromatic hydrocarbons (PAHs) and halide ions and therefore pose a great threat to high salt food safety. The aim is to explore the profiles of PAHs/XPAHs in market sausages and their formation during home cooking. Concentrations of PAH24 and XPAH18 in 36 market samples were 5.18-408.52 μg/kg and 0.05-0.41 μg/kg, respectively. Smoked sausages exhibited significantly higher concentrations of PAHs than non-smoked sausages. While ready-to-eat sausages presented notably higher XPAH levels than raw sausages. Furthermore, overcooking, such as baking at 220 °C, could result in an exaggerated increase in PAHs. Meanwhile, the increased chlorinated PAH levels after cooking indicated the unintentional formation of XPAHs during sausage cooking. Based on the ILCR model, the intake of 12.7 g/d for males and 10.8 g/d for females is the maximum threshold to achieve negligible risk levels (10-6).

Geographical origin traceability of mulberry leaves using stable hydrogen, oxygen, and carbon isotope ratios

Geographical discrimination of mulberry leaves is very important for their efficacy and quality as a traditional Chinese medicine. Stable hydrogen, oxygen, and carbon isotope ratios were measured in 292 mulberry leaves collected at 2 growth stages in 2 seasons from 8 regions of China. A stepwise linear discriminant analysis (LDA) approach were proposed to combine with stable isotope technology to tracing the origin of mulberry leaves. The results showed that leaves sampled in autumn were extremely depleted in 2H and 18O and slightly enriched in 13C compared with leaves sampled in summer, correlated with the effect of season, transpiration and photorespiration on stable isotopes. δ2H and δ18O of the leaves were enriched during the growth process. The overall discrimination accuracy of the autumn tender model was 81%, demonstrating that analysis of δ2H, δ18O, and δ13C is a promising technique for tracing the geographical origin of mulberry leaves, although season, growth stage and number of samples affect the accuracy of discrimination.

Determination of Four PAHs and Formaldehyde in Traditionally Smoked Chicken Products

The present study was conducted to analyze the level of four priority polycyclic aromatic hydrocarbons (PAHs), including benzo[a]pyrene (BaP), chrysene (Chr), benzo[a]anthracene (BaA), and benzo[b]fluoranthene (BbF), in traditionally smoked chicken products marketed in China. The results show that the amount of ƩPAH4 (the sum of four different PAHs: BaP, Chr, BaA, and BbF) was 30.43-225.17 and 18.75-129.54 µg/kg in the skin and meat of smoked chicken products, respectively. The content of ƩPAH4 in the smoked skin was significantly higher as compared to the smoked meat (p < 0.05). The calculation of MOE (margin of exposure) results suggested the possibilities of ingestion risk associated with the consumption of smoked chicken skin. Furthermore, the formaldehyde content in the skin of smoked chicken was 2.17-6.84 mg/kg and 0.86-2.95 mg/kg in the smoked meat. These results indicate that optimization or alternative methods for food processing should be developed to reduce the high level of harmful substances formed during processing to ensure the safety of smoked chicken products. Moreover, along with harmful substances, the moisture content and color of traditionally smoked chicken were analyzed to provide a practical reference for healthy, safe and green processing technology for smoked chicken.

Effect of Catechin on the Formation of Polycyclic Aromatic Hydrocarbons in Camellia oleifera Oil during Thermal Processing

Polycyclic aromatic hydrocarbons (PAHs) in oil are affected by many factors, including temperature, time, and PAHs precursors. Phenolic compounds, as beneficial endogenous components of oil, are often associated with the inhibition of PAHs. However, studies have found that the presence of phenols may lead to increased levels of PAHs. Therefore, this study took Camellia oleifera (C. oleifera) oil as the research object, in order to study the effect of catechin in the formation of PAHs under different heating conditions. The results showed that PAH4 were generated rapidly during the lipid oxidation induction period. When the addition of catechin was >0.02%, more free radicals were quenched than generated, thus inhibiting the generation of PAH4. ESR, FT-IR, and other technologies were employed to prove that when the catechin addition was <0.02%, more free radicals were produced than quenched, causing lipid damage and increasing PAHs intermediates. Moreover, the catechin itself would break and polymerize to form aromatic ring compounds, ultimately leading to the conclusion that phenolic compounds in oil may be involved in the formation of PAHs. This provides suggestions for the flexible processing of phenol-rich oil to balance the retention of beneficial substances, and for the safe control of hazardous substances in real-life applications.

Oxygenated polycyclic aromatic hydrocarbons in food: toxicity, occurrence and potential sources

Oxygenated polycyclic aromatic hydrocarbons (OPAHs) are polycyclic aromatic hydrocarbons (PAHs) functionalized with at least one carbonyl group and are generally thought to be more toxic than PAHs. In this review, the physical-chemical properties, toxicity, occurrence, and potential sources of OPAHs in food were comprehensively discussed. The toxicities of 1,2-naphthoquinone, 1,4-naphthoquinone, 6H-benzo[cd]pyren-6-one, benzo[a]anthracene-7,12-quinone and 9,10-phenanthrenequinone were prominent among the OPAHs. Both 1,4-naphthoquinone and 1,2-naphthoquinone exhibited strong genotoxicity, cytotoxicity, and developmental toxicity. 6H-benzo[cd]pyren-6-one and benzo[a]anthracene-7,12-quinone showed high genotoxicity and cardiovascular toxicity. Although 9,10-phenanthrenequinone showed no genotoxicity, it exhibited almost the strongest cytotoxicity. For the majority of foods, the concentrations of OPAHs and PAHs were on the same order of magnitude. OPAHs tend to be positively correlated with the corresponding PAH concentrations in oil and fried food, while for barbequed food and seafood, no obvious correlation was found. In addition, 9-fluorenone, 9,10-anthraquinone, benzanthrone and 1,2-acenaphthenequinone had high abundance in food. Environmental pollution, food composition, storage conditions, heating methods, and other treatments influence the accumulation of OPAHs in food. Furthermore, oxygen and water played an important role in the transformation from PAHs to OPAHs. In short, this review guides the evaluation and further reduction of OPAH-related health risks in food.

Migration and Distribution of PAH4 in Oil to French Fries Traced Using a Stable Isotope during Frying

Isotope-labeled four polycyclic aromatic hydrocarbons (PAH4-d12) were applied to study the migration and distribution of PAH4 in oil to French fries during frying. The results showed that the mobilities of PAH4-d12 showed a downtrend within 0-6 h and then an uptrend, and PAH4-d12 were mainly distributed in the crust of the French fries, especially five-ring PAHs-d12. The correlation analysis showed that PAH4-d12 migration was mainly caused by oil absorption of French fries. The low fluidity of the oil slowed down the PAH4-d12 migration, which was accelerated as the total polar component increased (higher than 15-20%). Additionally, higher frying temperature enhanced the crust ratio and porous structure of French fries, which explained the abundant five-ring PAHs-d12 distributed in the crust. This study provided references for optimizing the frying parameters: the exposure of PAH4 in French fries to humans can be reduced by controlling the oil quality and weakening the crust of the French fries.