RE: Beer benefits variably

[Guest guest]

Hops impart the bitter flavor tones more noticeable in micro-brews than mass

market beers. While the hops do not directly contribute to the fermentation

or conversion of sugars to alcohol, they are a preservative so may suppress

rouge colonization during the primary fermentation and improve shelf life

of the finished product, thus the high hop level in IPAs (India Pale Ales)

which were originally brewed to survive long ocean shipments during England's

more colonial days. Note: the IPAs were also higher alcohol content as that

also was preservative. Hops are also added in general to offset overly sweet

or malty flavors.

There are a number of different varieties of hop plants with notably

different flavor and no doubt chemical profiles. I'd take any

generalizations about " beer " with a whiskey chaser, :-) and like the red wine

claims I suspect the health impact of the alcohol (AFAIK good in

moderation) will swamp out whatever good effects from hops that may

result.

So while I won't drink any more or less because of this, if you want to max

out " your " hop intake from beer grab an India Pale Ale, properly chilled.

JR

-----Original Message-----

From:

[mailto: ]On Behalf Of Al Pater

Sent: Sunday, July 17, 2005 2:42 PM

Subject: [ ] Beer benefits variably

Hi All,

Beer drinking appears to confer different benefits relative to other alcoholic

drinks, since it is uniquely prepared using hops for of yeast for fermentation.

Benefits for some individuals may be greater than previously thought to be the

case.

See the related not pdf-accessible below.

Activation of Proestrogens from Hops (Humulus lupulus L.) by Intestinal

Microbiota;

Conversion of Isoxanthohumol into 8-Prenylnaringenin

Sam Possemiers, Arne Heyerick, Veerle Robbens, Denis De Keukeleire, and Willy

Verstraete

J. Agric. Food Chem., ASAP Article 10.1021/jf0509714 S0021-8561(05)00971-4. Web

Release Date: July 16, 2005

Hop, an essential ingredient in most beers, contains a number of

prenylflavonoids,

among which 8-prenylnaringenin (8-PN) would be the most potent phytoestrogen

currently known. Although a number of health effects are attributed to these

compounds, only a few reports are available about the bioavailability of

prenylflavonoids and the transformation potency of the intestinal microbial

community. To test these transformations, four fecal samples were incubated with

xanthohumol, isoxanthohumol (IX), and 8-PN. Upon incubation with IX, present in

strong ales up to 4 mg/L, 36% was converted into 8-PN in one fecal sample and

the

estrogenic properties of the sample drastically increased. In an experiment with

12

fecal cultures, this conversion was observed in one-third of the samples,

indicating

the importance of interindividual variability in the intestinal microbial

community.

Eubacterium limosum was identified to be capable of this conversion

(O-demethylation) of IX into 8-PN, and after strain selection, a conversion

efficiency of 90% was achieved. Finally, strain supplementation to a

nonconverting

fecal sample led to rapid and high 8-PN production at only 1% (v/v) addition. Up

to

now, the concentration of 8-PN in beer was considered too low to affect human

health. However, these results show that the activity of the intestinal

microbial

community could more than 10-fold increase the exposure concentration. Because

prenylflavonoids are present in many beers with IX being the major constituent,

the

results raise the question whether moderate beer consumption might contribute to

increased in vivo levels of 8-PN and even influence human health.

Al Pater, PhD; email: old542000@...

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