Standardized methods for the determination of antioxidant capacity and phenolics in foods and dietary supplements

Ronald L. Prior, Xianli Wu, Karen Schaich

Research output: Contribution to journalReview articlepeer-review

3482 Scopus citations


Methods available for the measurement of antioxidant capacity are reviewed, presenting the general chemistry underlying the assays, the types of molecules detected, and the most important advantages and shortcomings of each method. This overview provides a basis and rationale for developing standardized antioxidant capacity methods for the food, nutraceutical, and dietary supplement industries. From evaluation of data presented at the First International Congress on Antioxidant Methods in 2004 and in the literature, as well as consideration of potential end uses of antioxidants, it is proposed that procedures and applications for three assays be considered for standardization: the oxygen radical absorbance capacity (ORAC) assay, the Folin-Ciocalteu method, and possibly the Trolox equivalent antioxidant capacity (TEAC) assay. ORAC represent a hydrogen atom transfer (HAT) reaction mechanism, which is most relevant to human biology. The Folin-Ciocalteu method is an electron transfer (ET) based assay and gives reducing capacity, which has normally been expressed as phenolic contents. The TEAC assay represents a second ET-based method. Other assays may need to be considered in the future as more is learned about some of the other radical sources and their importance to human biology.

Original languageEnglish (US)
Pages (from-to)4290-4302
Number of pages13
JournalJournal of agricultural and food chemistry
Issue number10
StatePublished - May 18 2005

All Science Journal Classification (ASJC) codes

  • Chemistry(all)
  • Agricultural and Biological Sciences(all)


  • Antioxidant capacity
  • Dietary supplements
  • Folin-Ciocalteu method
  • Foods
  • Nutraceuticals
  • ORAC
  • Standardized methods
  • TEAC


Dive into the research topics of 'Standardized methods for the determination of antioxidant capacity and phenolics in foods and dietary supplements'. Together they form a unique fingerprint.

Cite this