Monday, October 7, 2013

Application of DPPH absorbance method to monitor the degree of oxidation in thermally-oxidized oil model system with antioxidants

JuDong Yeo, Min Kyu Jeong, JaeHwan Lee

                                                                                         

Abstract

Changes of 2,2-diphenyl-1-picrylhydrazyl (DPPH) absorbance were monitored in thermally-oxidized lard containing free radical scavengers (FRSs). Hydrogen donating abilities of α-tocopherol to DPPH were higher than those of sesamol and butylated hydroxyanisole (BHA), indicating reactivity of DPPH and FRSs in lard depends on the types of FRSs. For the first 20 min oxidation, DPPH absorbance from lard with 3.38 μmol/g α-tocopherol, sesamol, and BHA increased by 0.324, 0.240, and 0.313, respectively while those from lard without FRS decreased by 0.350. Results of conjugated dienoic acid (CDA), and p-anisidine value (p-AV) showed that antioxidative activity were high in the order of sesamol, BHA, and α-tocopherol, which implies that hydrogen donating abilites of FRSs may not be the most critical factor to determine antioxidant effectiveness. Monitoring DPPH absorbance in oxidized lard with FRS could be useful indicators for comparing antioxidative ability of FRSs.

source: visit here

Keywords:antioxidant effectiveness,2,2-diphenyl-1-picrylhydrazyl (DPPH),thermal oxidation,antioxidant.

 
^Top
Click Here to submit Your Abstract to get Indexed by NTHRYS