2.9. Determinati on of antioxidant capacity of apple juice
2.9.1. Assay of antioxidant capacity
Antioxidant capacity of apple juice was measured according to
the method reported by Prieto et al. [14]. Aknown aliquot
(0.4 mL,250 lg/mL in methanol) of juice sample was taken in a
vial, and then 4.0 mL of reagent solution containing 0.6 Msulfuric
acid, 28 mM sodium phosphat e and 4mM ammonium molybdate
was added. The mixture was held for 90 min in awater bath at
95 C. 4mL of the reagent solution and 0.4 mL of methanol was ta-
ken in a vial to run ablank.The absorbance of mixture was mea-
sured at 695 nm after cooling to room temperature using a
spectrophot ometer against the blank.Ascorbic acid was used as
the standard and antioxidant capacity was expressed relative to
ascorbic acid.