Drinking beer can improve bone strength
8 February 2010
Beer drinkers will be pleased to learn that a new study
suggests that beer is a significant source of dietary silicon, a key
ingredient for increasing bone mineral density.
Researchers from the Department of Food Science & Technology at the
University of California, Davis studied commercial beer production to
determine the relationship between beer production methods and the
resulting silicon content, concluding that beer is a rich source of
dietary silicon.
Details of this study are available in the February issue of the
Journal of the Science of Food and Agriculture, published by
Wiley-Blackwell on behalf of the Society of Chemical Industry [1].
“The factors in brewing that influence silicon levels in beer have
not been extensively studied,” said Charles Bamforth, lead author of the
study. “We have examined a wide range of beer styles for their silicon
content and have also studied the impact of raw materials and the
brewing process on the quantities of silicon that enter wort and beer.”
Silicon is present in beer in the soluble form of orthosilicic acid
(OSA), which yields 50% bioavailability, making beer a major contributor
to silicon intake in the Western diet.
According to the US National Institutes of Health (NIH), dietary
silicon (Si), as soluble OSA, may be important for the growth and
development of bone and connective tissue, and beer appears to be a
major contributor to Si intake. Based on these findings, some studies
suggest moderate beer consumption may help fight osteoporosis, a disease
of the skeletal system characterized by low bone mass and deterioration
of bone tissue.
The researchers examined a variety of raw material samples and found
little change in the silicon content of barley during the malting
process. The majority of the silicon in barley is in the husk, which is
not affected greatly during malting.
The malts with the higher silicon contents are pale coloured which
have less heat stress during the malting process. The darker products,
such as the chocolate, roasted barley and black malt, all have
substantial roasting and much lower silicon contents than the other
malts for reasons that are not yet known.
The hop samples analyzed showed surprisingly high levels of silicon
with as much as four times more silicon than is found in malt. However,
hops are invariably used in a much smaller quantity than is grain.
Highly hopped beers, however, would be expected to contain higher
silicon levels.
No silicon was picked up from silica hydrogel used to stabilize beer,
even after a period of 24 hours and neither is there pick up from
diatomaceous earth filter aid.
The study also tested 100 commercial beers for silicon content and
categorized the data according to beer style and source. The average
silicon content of the beers sampled was 6.4 to 56.5 mg/L.
“Beers containing high levels of malted barley and hops are richest
in silicon,” concludes Dr. Bamforth. “Wheat contains less silicon than
barley because it is the husk of the barley that is rich in this
element. While most of the silicon remains in the husk during brewing,
significant quantities of silicon nonetheless are extracted into wort
and much of this survives into beer.”
Reference
1. Troy R. Casey and Charles W. Bamforth. Silicon in Beer and
Brewing. Journal of the Science of Food and Agriculture.
Published Online: February 8, 2010 (DOI: 10.1002/JSFA.3884); Print Issue
Date: February 2010.