Re: Rhubarb OK to eat in autumn?

"David Hare-Scott" <compost@xxxxxxxxxxx> wrote in message
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"David E. Ross" <nobody@xxxxxxxxxxx> wrote in message
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Raw rhubarb is quite toxic. Cooked stalks are quite delicious.

--

I presume that you mean the stems not the leaves. I haven't heard this
before, what poison is in it that is removed by cooking? Do you have any
evidence of the toxicity of uncooked stems versus cooked?

This ref is fairly comprehensive but doesn't mention it.

http://www.rhubarbinfo.com/rhubarb-poison.html#TOC82

David



"Rhubarb leaves contain oxalic acid, a corrosive and nephrotoxic acid that
is present in many plants. The LD50 (median lethal dose) for pure oxalic
acid is predicted to be about 375 mg/kg body weight,[citation needed] or
about 25 g for a 65 kg (~140 lb) human. While the oxalic acid content of
rhubarb leaves can vary, a typical value is about 0.5%,[5] so a rather
unlikely five kilograms of the extremely sour leaves would have to be
consumed to reach an LD50 dose of oxalic acid."

Perhaps the unpleasant, but minor effects of the oxalic acid are enough to
convince people that eating too much wouldn't be such a great idea. Sort of
like the stink added to propane as a warning.


.

Relevant Pages

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