## 2 PAH Sample Pretreatment in Food and Quantitative Analysis  
Sample preparation requires comprehensive extraction followed by purification before detection [26], entailing consistent improvement, as well as alternative approaches [2]. To provide repeatable data and satisfy legal criteria, proper sample preparation is necessary. Taking into account the complexity of food matrices, as well as the trace quantities of PAH molecules in comparison to other constituents, sample pretreatment translates into laborious and time-consuming tasks [15; 27; 28]. The most common PAH extraction methods include Soxhlet extraction, ultrasonication, and stirring/agitation [2]. The outcomes of these techniques usually involve large amounts of solvent and significant measurement errors [15; 29]. Given the advancement toward more sensitive and accurate analytical techniques, the development of sample preparation processes has gained increasing attention. Automated equipment, shorter analytical times, greater quality, environmentally friendly processes, and smaller sample sizes are all benefits of technique optimization [25; 26; 28]. Modern extraction techniques for PAHs in food have achieved popularity through their increased efficiency and include pressurized liquid extraction (PLE), microwave-assisted extraction (MAE), supercritical fluid extraction (SFE), high-temperature distillation (HTD), and fluidized-bed extraction (FBE) [2; 13; 25; 30]. The purification step is commonly achieved by column chromatography, gel permeation chromatography (GPC), or solid-phase extraction (SPE), along with dispersive liquid-liquid microextraction (DLLME), solid-phase microextraction (SPME), magnetic solid-phase extraction (MSPE), and QuEChERS [2; 13; 25; 28]. The advantages of these techniques include lower cost, less solvent, time savings, and increased yield through selective interaction with the molecules, thus ensuring great extraction performance [30; 31]. The QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) method was first developed to screen pesticides in diverse food and agricultural products [32]. The original QuEChERS approach is aimed at simplifying the extraction and clean-up steps, as compared to time-consuming and laborious conventional procedures [33]. In recent years, the QuEChERS strategy has been persistently adjusted and systematically employed in routine analytical determinations [13; 34]. Its foundation is based on dispersive solid-phase extraction (dSPE) to remove potentially interfering compounds (fats, pigments, sugars, etc.). Apart from multi-residue pesticide analysis, the method has been successfully implemented in food and environmental matrices to separate various target analytes, including mycotoxins, antibiotics, persistent organic pollutants (POPs), hormones, and PAHs, consistently attaining high selectivity, sensitivity, and specificity [2; 13; 28; 34]. In addition to the original unbuffered method involving an optimal 1:4 ratio of the two salts (MgSO\({}_{4}\) and NaCl) for partitioning [32; 35], two modified QuEChERS methods were established: (a) the EN official method--BS EN 15662:2008 standard (withdrawn) revised in 2018 [36], employing the addition of a citrate buffer (1 g of trisodium citrate dihydrate and 0.5 g of disodium hydrogen citrate sesquihydrate); (b) the AOAC official method [37], applying the addition of an acetate buffer (1.5 g of sodium acetate) and 6 g of MgSO\({}_{4}\) instead of 4 g.  
In the purification process, MgSO\({}_{4}\) is used as a drying agent, whereas a primary secondary amine (PSA) is typically applied as a weak anion exchanger targeting the removal of fatty acids, sugars, organic acids, lipids, sugars, and some pigments [33; 34]. Besides PSA and MgSO\({}_{4}\), the major sorbents employed are octadecyl silica (C18), which is able to hold vitamins and minerals and is highly effective in removing fats, and graphitized carbon black (GCB), which is effective in eliminating co-extracted pigments (e.g., carotenoids and chlorophyll) [34].