Thursday, 22 July, 2004
The US military has devised a way
to ensure its troops in battle need never go hungry - with dried food that can
by rehydrated using dirty water or urine.
The
meal comes in a pouch that filters out 99.9% of bacteria and most toxic
chemicals, says New Scientist magazine.
The
aim is to reduce the amount of water soldiers need to carry.
The
firm behind it says soldiers should only use urine as last resort - as the
membrane can not filter out urea, which in the long term causes kidney damage.
"The
pouch - containing chicken and rice - relies on osmosis to filter the water or
urine," the New Scientist Magazine reported.
The
liquid passes through a membrane, thin sheets of a cellulose-based plastic with
gaps just 0.5 nanometres wide.
It
means only clean water can reach the food, and the bacteria is left behind.
'Indestructible
sandwich'
The
idea has come from the Combat Feeding Directorate, part of the US Army Soldier
Systems Center in Natick, Massachusetts.
The
organisation is also the brains behind the "indestructible sandwich",
which can stay fresh for three years.
A
spokeswoman said the dehydrated pouches would reduce the current weight of
3.5kg for a day's food supply of three meals, to 0.4kg.
But
Hydration Technology Inc, in Albany, Oregon, which made the membrane, warned it
is too coarse to filter out urea so soldiers should only use urine in an
absolute emergency.
Engineer Ed Beaudry was quoted by
the New Scientist as saying that the body would not find using urine to
rehydrate food toxic in the short term, but in the long term it would cause
kidney damage.
http://newsvote.bbc.co.uk/mpapps/pagetools/print/news.bbc.co.uk/2/hi/americas/3915659.stm