Abstract:

Purpose: To develop a phenanthroline-Fe2+ method for determining the antioxidant capacity of healthcare foods. Methods: Trolox was used as the reference substance for antioxidant capacity assessment. Some key determination conditions such as hydrogen peroxide amount, color development time, solvent type, etc were optimized. Method figures of merits including linearity, limit of detection, precision, repeatability and spike recovery were investigated. Results: The developed method presented good linearity when trolox concentration varied from 0.01 to 0.15g/L, with a limit of detection of 0.0050 g/L, a parallel precision (375 ± 12) μmol/g (3.2% variation coefficient), a repeated precision of (365 ± 16) μmol/g (4.4% variation coefficient), and an average spike recovery of (98.0 ± 2.4)% (n = 5). Conclusions: This method is applicable to the determination of antioxidant capacity of healthcare foods.

Key words: healthcare foods, antioxidant capacity, phenanthroline- Fe2+ method