title: Monitoring changes in acid value, total polar material, and antioxidant capacity of oils used for frying chicken.
abstract: Oxidation products and tocol homologues were monitored in oils during chicken frying to determine the discarding point of highly used frying oils. Oils were heated without chicken for 170h while chicken frying was performed 130 cycles at 180°C. As heating time and frying cycles increased, all oxidation parameters including acid value, total polar materials (TPM), conjugated dienoic acid (CDA), and p-anisidine values (p-AV) increased significantly (p<0.05). γ-Tocopherol and γ-tocotrienol had the lowest stability in oils during heating or frying processes compared to other tocol homologues. TPM values over 24% were obtained after about 109h for heated oil and 100 cycles for oils used to fry chicken. A decrease of 2,2-diphenyl-1-picrylhydrazyl (DPPH) in isooctane and methanol was highly correlated with the formation of TPM in oils during the frying process. Both DPPH loss and TPM values could be applied to determine the discarding points of highly used frying oils.
authors.affiliation: Department of Food Science and Biotechnology, Sungkyunkwan University, Suwon, Republic of Korea.
authors.forename: JuHee
authors.initials: J
authors.lastname: Song
authors.affiliation: Department of Food and Nutrition, Kangwon National University, Samcheok, Republic of Korea.
authors.forename: Mi-Ja
authors.initials: MJ
authors.lastname: Kim
authors.affiliation: Food Safety Center, OTTOGI Corporation, Gunpo, Republic of Korea.
authors.forename: Young-Jun
authors.initials: YJ
authors.lastname: Kim
authors.affiliation: Department of Food Science and Biotechnology, Sungkyunkwan University, Suwon, Republic of Korea. Electronic address: s3hun@skku.edu.
authors.forename: JaeHwan
authors.initials: J
authors.lastname: Lee
mesh_terms: D000143:Acids / Q000737:chemistry*; D000814:Aniline Compounds / Q000032:analysis; D000818:Animals; D000975:Antioxidants / Q000737:chemistry*; D001713:Biphenyl Compounds / Q000032:analysis; D002645:Chickens; D002839:Chromans / Q000032:analysis; D003296:Cooking; D006358:Hot Temperature; D010084:Oxidation-Reduction; D010851:Picrates / Q000032:analysis; D010938:Plant Oils / Q000737:chemistry*; D011200:Poultry; D014810:Vitamin E / Q000031:analogs & derivatives / Q000032:analysis; D024504:gamma-Tocopherol / Q000032:analysis
chemical_list: D000143:Acids; D000814:Aniline Compounds; D000975:Antioxidants; D001713:Biphenyl Compounds; D002839:Chromans; D010851:Picrates; D010938:Plant Oils; D014810:Vitamin E; C013649:plastochromanol 8; C013813:4-anisidine; D024504:gamma-Tocopherol; C004931:1,1-diphenyl-2-picrylhydrazyl
keywords: Chicken; DPPH loss; Frying; Oxidation parameter; Total polar material