Consumers should be warned about the dangers of eating untreated bitter lupin beans after two people who consumed products containing the beans became ill with anticholinergic syndrome, according to an article in the Medical Journal of Australia.
Lupins are a legume or pulse, and commonly eaten species may be either sweet or bitter. Sweet lupin flour is increasingly being added to bread to reduce glyaecemic index and reduce energy intake, and to sausages to decrease fat intake. Bitter lupins can also be eaten, but need to be treated first to remove excessive and dangerous levels of toxic alkaloids.
Two women presented separately to a West Australian metropolitan hospital in September 2007 when they became ill after eating products which contained bitter lupin flour purchased from the same chain of grocery stores. Symptoms included dry mouth, lethargy, difficulty mobilising, blurred vision and light-headedness.
Subsequent investigations revealed that, when the supply of sweet lupin flour was exhausted, a quantity of bitter lupins had been milled into flour, which was distributed to a number of stores.
The lupin beans contained 1000 times the alkaloid level of flour permitted under the Australia New Zealand Food Standards Code.
Ms Nevada Pingault, an Epidemiologist at WA Health’s Communicable Disease Control Directorate, said failure to remove alkaloids from lupins could result in lupin toxicity, manifesting as anticholinergic syndrome.
"Fortunately, neither of the two women who presented to hospital became seriously ill. But lupin poisoning can be fatal," Ms Pingault said.
"In light of the increasing consumption of lupin products, we recommend that information be provided to food suppliers and consumers about the dangers of selling and eating products containing bitter lupins that have not been appropriately treated to remove toxic alkaloids.
"Doctors should question patients who present with symptoms of anticholinergic syndrome about their recent food consumption, particularly consumption of products which contain lupin."
The Medical Journal of Australia is a publication of the Australian Medical Association.
(Source: Australian Medical Association: Medical Journal of Australia: August 2009)