“…To the best of our knowledge, the majority of studies conducted in Iran (Aalipour Hafshejani, Mahdavi, & Aalipour Hafshejani, ; Arbabi & Deris, ; Farrokhzadeh et al, ; Hassanzadazar, Ghayurdoost, Aminzare, Mottaghianpour, & Taami, ; Mohammadi, Hajeb, Seyyedian, Hossein Mohebbi, & Barmak, ; Navab Daneshmand & Ghavami, ; Pourmahmoudi, Akbartabar Turi, Poursamad, Sadat, & Karimi, ) have determined the frying oils’ rancidity by their peroxide value (PV). However, this study, for the first time, was conducted to do the analysis based on a set of physicochemical parameters (PV, free fatty acids [FFA], p ‐anisidine value [ p ‐AV], total oxidation [TOTOX] value, red color, total polar compounds [TPC], and viscosity) and compared to the standard values reported by American Oil Chemists’ Society (AOCS), International Organization for Standardization (ISO), and Institute of Standards and Industrial Research of Iran (ISIRI) to evaluate the rancidity and quality of discarded frying oils in fast food restaurants and also to measure the amounts of their SFAs, TFAs, and heavy metal pollutants.…”