Anhydrous sodium sulfate

Milli-Q equipment (Millipore, Bedford, MA, USA) allowed for obtaining ultra-pure water. Super-gradient High-Performance Liquid-Chromatography (HPLC) grade acetonitrile and methanol were from Scharlau (Sentmenat, Spain). Ammonium chloride was from Merck (Darmstadt, Germany). Individual L-α amino acids and diethylethoxymethylenemalonate were from Acros Organics (New Jersey, NJ, USA). Amino acid solutions were made with HCl 0.1 N. Dichloromethane, n-pentane and anhydrous sodium sulfate were from Scharlau (Sentmenat, Spain). Standards for volatile compounds were from Merck (Madrid, Spain), Aldrich (Madrid, Spain), Fluka (Seelze, Germany), Alfa Aesar (Barcelona, Spain) and Sigma (Madrid, Spain). All the standards were prepared in 50% hydroalcoholic solutions.

For the preparation of food samples, potassium hydroxide, dichloromethane, methanol, anhydrous sodium sulfate, n‐hexane were purchased from Scharlau, while sodium sulfide nonahydrate and HPLC grade acetonitrile were from Sigma‐Aldrich. PAH standards: naphthalene, fluoranthene, and phenanthrene from Fluka, fluorene from Alfa Aesar, pyrene from Hopkins Williams LTD, and anthracene from BDH. Silica gel 60 with 70–230 mesh size was obtained from Merck. The rabbit for sample preparation was purchased from the supermarket of Faisalabad, Pakistan. The 36 samples of meat (foreleg, back, and hind leg) were prepared by frying.