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Author Food destroys antioxidants
ironjustice@aol.com

2005-08-15, 10:54 pm

Effects of iron, ascorbate, meat and casein on the antioxidant capacity
of green tea under conditions of in vitro digestion

Isidora Alexandropoulou, Michael Komaitis and Maria Kapsokefalou,

Department of Food Science and Technology, Agricultural university of
Athens, Iera Odos 75, Athens 11855, Greece

Received 12 July 2004; revised 16 November 2004; accepted 16 November
2004. Available online 9 February 2005.

Abstract
The hypothesis that interactions of dietary polyphenols with dietary
iron occur during digestion and result in a decrease of the
post-absorptive antioxidant properties of polyphenols was investigated.
The hypothesis was tested in vitro, under conditions that simulate
gastrointestinal digestion. Mixtures of green tea, iron, and three
dietary factors that modify the form of iron in the lumen, namely
ascorbic acid, meat or casein, were subjected to an in vitro
gastrointestinal digestion. Antioxidant capacity (FRAP assay), iron
concentration (ferrozine assay) and polyphenol concentration
(Folin-Ciocalteau assay) were measured in the in vitro digests. The
presence of iron decreased the antioxidant capacity and the polyphenol
concentration of green tea digests. The presence of ascorbic acid
increased, while meat and casein decreased the antioxidant capacity of
green tea. The factorial analysis of the data suggests that protein and
iron interact with green tea polyphenols during the in vitro digestion
and decrease their antioxidant capacity. These results support the
aforementioned hypothesis.

Keywords: Antioxidant; Green tea; Iron; In vitro; Polyphenols



Corresponding author. Tel./fax: +30 210 5294708



Food Chemistry
Volume 94, Issue 3 , February 2006, Pages 359-365

Barry

2005-08-15, 10:54 pm

I've wondered whether putting lemon in my green tea made it healthier
or not. It sounds like the lemon's ascorbic acid might make it
healthier.

I wonder how long in vitro digestion of meat and milk takes, before
green tea has it's full beneficial effect.

Mortimer Schnerd, RN

2005-08-15, 10:54 pm

Barry wrote:
> I've wondered whether putting lemon in my green tea made it healthier
> or not. It sounds like the lemon's ascorbic acid might make it
> healthier.
>
> I wonder how long in vitro digestion of meat and milk takes, before
> green tea has it's full beneficial effect.



barry@polisource.com

2005-08-15, 10:54 pm

Mortimer Schnerd, RN wrote:[vbcol=seagreen]
> Barry wrote:

Is that all you have to say or did something go wrong?

Not that repeating me is a bad thing.

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