Assay dilution factors confound measures of total antioxidant capacity in polyphenol-rich juices.

  title={Assay dilution factors confound measures of total antioxidant capacity in polyphenol-rich juices.},
  author={Bradley W. Bolling and Ya-Yen Chen and Alison G Kamil and C-Y Oliver Chen},
  journal={Journal of food science},
  volume={77 2},
UNLABELLED The extent to which sample dilution factor (DF) affects total antioxidant capacity (TAC) values is poorly understood. Thus, we examined the impact of DF on the ORAC, FRAP, DPPH, and total phenols (TP) assays using pomegranate juice (PJ), grape juice (GJ), selected flavonoids, ascorbic acid, and ellagic acid. For ORAC, GJ was comparable to PJ at DF 750, but at DF 2000, the ORAC value of GJ was 40% more than PJ. Increasing DF increased GJ and PJ, DPPH, TP, and FRAP values 11% and 14… 

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