Polycyclic aromatic hydrocarbons in edible oils and fatty foods: Occurrence, formation, analysis, change and control

Efficient removal of PAHs from peanut oil using coconut shell-based activated charcoal decorated by cationic (CTAB), anionic (SDS), non-ionic surfactant (Triton X-100)

The coconut shell-based activated charcoal was decorated by three different electronegativities of surfactants (CTAB, SDS, and Triton X-100) through the impregnation method, and the decorated activated charcoal adsorbents were used for the removal of PAHs from peanut oil, respectively. The influence of surfactant decoration on the adsorption and detoxification effect of coconut shell-based activated charcoal was discussed. The thermodynamic and kinetic behaviors of PAHs adsorption on the surfactant-modified activated charcoal were investigated, and the adsorption mechanism was analyzed in-depth. Notably, the prepared modified coconut shell activated charcoal could not only remove more than 90% of PAHs from the peanut oil but also keep the cytotoxicity of the treated peanut oil low. Meanwhile, the detoxification procedure has little effect on the nutritional quality and flavor of the peanut oil. The results of this fundamental study demonstrate that the low-cost surfactant-modified coconut shell-based activated charcoal was effective and feasible.

Methods of Minimizing Polycyclic Aromatic Hydrocarbon Content in Homogenized Smoked Meat Sausages Using Different Casings and Variants of Meat-Fat Raw Material

To ensure food safety and protect human health, the levels of polycyclic aromatic hydrocarbon (PAH) contamination in model smoked-pork meat products were examined to select which type of casing and variant of raw material contributes to minimizing the content of PAHs in the final products. The sausages were smoked in a steam smoke chamber with an external smoke generator. The determination of PAHs was performed using the QuEChERS-HPLC-FLD/DAD method. The analyzed products met the requirements of Commission Regulation (EU) No. 835/2011 on the maximum permissible levels of PAHs. Statistically higher sums of 19 PAHs, including 15 heavy and 4 marker PAHs, were stated in smoked sausages in natural and cellulose casings. Synthetic casings like collagen and polyamide exhibited better barriers against PAH contamination than cellulose and natural casings. For each type of casing, significantly higher concentrations of PAHs were found in the external parts of the products. An increase in the fat content of the raw material increased the levels of PAH contamination in the products, regardless of the casing. Therefore, in industrial practice, the selection of an appropriate type of casing and raw material with the lowest possible fat content can be an effective method for reducing PAH levels in the interior of smoked meat products.

Biodegradation mechanisms of polycyclic aromatic hydrocarbons: Combination of instrumental analysis and theoretical calculation

Polycyclic aromatic hydrocarbons (PAHs) are a common class of petroleum hydrocarbons, widely encountered in both environment and industrial pollution sources. Owing to their toxicity, environmental persistence, and potential bioaccumulation properties, a mounting interest has been kindled in addressing the remediation of PAHs. Biodegradation is widely employed for the removal and remediation of PAHs due to its low cost, lack of second-contamination and ease of operation. This paper reviews the degradation efficiency of degradation and the underlying mechanisms exhibited by algae, bacteria, and fungi in remediation. Additionally, it delved into the application of modern instrumental analysis techniques and theoretical investigations in the realm of PAH degradation. Advanced instrumental analysis methods such as mass spectrometry provide a powerful tool for identifying intermediates and metabolites throughout the degradation process. Meanwhile, theoretical calculations could guide the optimization of degradation processes by revealing the reaction mechanisms and energy changes in PAH degradation. The combined use of instrumental analysis and theoretical calculations allows for a comprehensive understanding of the degradation mechanisms of PAHs and provides new insights and approaches for the development of environmental remediation technologies.

Liquid Interfacial Coassembly of Plasmonic Arrays and Trace Hydrophobic Nanoplastics in Edible Oils for Robust Identification and Classification by Surface-Enhanced Raman Spectroscopy

The ubiquity of micro-/nanoplastics poses a visible threat to the environment, aquatic organisms, and human beings and has become a global concern. Here, we proposed a liquid interface-based strategy using surface-enhanced Raman spectroscopy to coassemble nanoplastics and gold nanoparticles into a dense and homogeneous plasmonic array, thereby enabling the rapid and sensitive detection of trace nanoplastics. In addition, due to the uniqueness of the oil-water immiscible two-phase interface, we achieved ideal results for the detection of nanoplastics in a complex matrix (e.g., aqueous environment and edible oil) with a detection limit of μg/mL. With the aid of the principal component analysis algorithm, the differentiation and identification of multiple nanoplastic components (e.g., polystyrene, polyethylene, and polyethylene terephthalate) in aqueous environments and common hazards (e.g., Bap and Phe) in edible oil were achieved. Therefore, our self-assembled plasmonic arrays are expected to be used for monitoring environmental pollution and food safety.

Enzymatic Treatments for Biosolids: An Outlook and Recent Trends

Wastewaters are nutrient-rich organic materials containing significant concentrations of different nutrients, dissolved and particulate matter, microorganisms, solids, heavy metals, and organic pollutants, including aromatic xenobiotics. This variety makes wastewater treatment a technological challenge. As a result of wastewater treatment, biosolids are generated. Biosolids, commonly called sewage sludge, result from treating and processing wastewater residuals. Increased biosolids, or activated sludge, from wastewater treatment is a major environmental and social problem. Therefore, sustainable and energy-efficient wastewater treatment systems must address the water crisis and environmental deterioration. Although research on wastewater has received increasing attention worldwide, the significance of biosolids treatments and valorization is still poorly understood in terms of obtaining value-added products. Hence, in this review, we established some leading technologies (physical, chemical, and biological) for biosolids pretreatment. Later, the research focuses on natural treatment by fungal enzymes to end with lignocellulosic materials and xenobiotic compounds (polyaromatic hydrocarbons) as a carbon source to obtain biobased chemicals. Finally, this review discussed some recent trends and promising renewable resources within the biorefinery approach for bio-waste conversion to value-added by-products.

Monitoring and Occurrence of Heavy PAHs in Pomace Oil Supply Chain Using a Double-Step Solid-Phase Purification and HPLC-FLD Determination

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental and processing contaminants generated by both spontaneous and anthropogenic incomplete combustion processes of organic matter. Contamination of PAHs in vegetable oils can result from several factors and processes, including environmental contamination, oil processing, and migration from food contact materials. The determination of PAHs in edible oil presents a challenge because of the complexity of the matrix. Since PAHs are present at lower levels than triglycerides, it is necessary to isolate the compounds of interest from the rest of the matrix. To this purpose, a new purification approach based on a double solid-phase extraction (SPE) step followed by high performance liquid chromatography–fluorometric detector (HPLC-FLD) analysis was developed. The method involves a first purification step by using a 5 g silica SPE cartridge, previously washed with dichloromethane (20 mL), dried completely, and then conditioned with n-hexane (20 mL). The triglycerides are retained by the silica, while the PAH-containing fraction is eluted with a mixture of n-hexane/dichloromethane (70/30, v/v). After evaporation, the residue is loaded on a 5 g amino SPE cartridge and eluted with n-hexane/toluene (70/30, v/v) before HPLC-FLD analysis. The focus was the evaluation of the contribution of the various phases of the pomace oil supply chain in terms of the heavy PAHs (PAH8) concentration. Data collected showed that pomace contamination increased (by 15 times) as storage time increased. In addition, the process of pomace drying, which is necessary to reduce its moisture content before solvent extraction of the residual oil, appeared to significantly contribute to the total heavy PAHs content, with increases in value by up to 75 times.

Critical Evaluation of Analytical Methods for the Determination of Anthropogenic Organic Contaminants in Edible Oils: An Overview of the Last Five Years

Anthropogenic contaminants, as pesticides, polycyclic aromatic hydrocarbons (PAHs) and monochloropropanediols (MCPDs), have become important to be controlled in edible oils, since their regular occurrence. In fact, alerts from the Rapid Alert System for Food and Feed (RASFF) in oils normally include these compounds. From a critical point of view, tools used to control these compounds in the last 5 years will be discussed, including sample preparation, analysis and current regulations. Extraction and analysis methods will be discussed next, being liquid-liquid extraction (LLE) and QuEChERS, with or without clean-up step, as well as chromatographic methods coupled to different analyzers (mainly mass spectrometry), the most commonly used for extraction and analysis respectively. Occurrence in samples will also be reviewed and compared with the legal maximum residue limits (MRLs), observing that 4%, 20% and 60% of the analyzed samples exceed the legal limits for pesticides, MCPDs and PAHs respectively.