Whole grain antioixidants underestimated?

[esoteric17]

I know this study is from 2004 and most of the values here are from the USDA 2007 study, but wouldn't they have measured all foods the same and not measuring the "bound" form mentioned here?

http://www.infozine.com/news/stories/op ... /sid/4184/

[Fagopyrum]

Just want to comment the headline "Whole grain antioxidants underestimated?". The answer to the question is yes. In the published ORAC method, only the soluble antioxidants are measured. About 90 % of the phenolic acids are esterified into insoluble bound form. However, this bound antioxidant reserve is at least partly bioavailable in our GI tract. According our preliminary work, a certain oat cookie had ORAC value around 1 200. The ORAC value of the insoluble bound phenolic acid -fraction (liberated by alkali treatment) was around 700. So the total ORAC value of the oat cookie would be 1 900. This was actually a little disappointment to me, since I expected the contribution of the bound phenolic acids to be much more.

[esoteric17]

Just want to comment the headline "Whole grain antioxidants underestimated?". The answer to the question is yes. In the published ORAC method, only the soluble antioxidants are measured. About 90 % of the phenolic acids are esterified into insoluble bound form. However, this bound antioxidant reserve is at least partly bioavailable in our GI tract. According our preliminary work, a certain oat cookie had ORAC value around 1 200. The ORAC value of the insoluble bound phenolic acid -fraction (liberated by alkali treatment) was around 700. So the total ORAC value of the oat cookie would be 1 900. This was actually a little disappointment to me, since I expected the contribution of the bound phenolic acids to be much more.

Very interesting - thanks for the information!