Red Kidney Bean Poisoning

FryBoy

New member
My wife was reading up on slow cookers and came across several articles warning about the potential danger of uncooked or insufficiently cooked red kidney beans. News to me, and I thought others might be interested, too.

The information below is from the FDA's food reference site, but also see this page for a bit more information: http://www.fda.gov/food/foodsafety/...thogensnaturaltoxins/badbugbook/ucm071092.htm

RED KIDNEY BEAN POISONING

Red Kidney Bean Poisoning is an illness caused by a toxic agent, Phytohaemagglutnin (Kidney Bean Lectin). This toxic agent is found in many species of beans, but it is in highest concentration in red kidney beans (Phaseolus vulgaris). The unit of toxin measure is the hemagglutinating unit (hau). Raw kidney beans contain from 20,000 to 70,000 hau, while fully cooked beans contain from 200 to 400 hau. White kidney beans, another variety of Phaseolus vulgaris, contain about one-third the amount of toxin as the red variety; broad beans (Vicia faba) contain 5 to 10% the amount that red kidney beans contain.

As few as 4 or 5 beans can bring on symptoms. Onset of symptoms varies from between 1 to 3 hours. Onset is usually marked by extreme nausea, followed by vomiting, which may be very severe. Diarrhea develops somewhat later (from one to a few hours), and some persons report abdominal pain. Some persons have been hospitalized, but recovery is usually rapid (3 - 4 h after onset of symptoms) and spontaneous.

The syndrome is usually caused by the ingestion of raw, soaked kidney beans, either alone or in salads or casseroles. As few as four or five raw beans can trigger symptoms. Several outbreaks have been associated with "slow cookers" or crock pots, or in casseroles which had not reached a high enough internal temperature to destroy the glycoprotein lectin. It has been shown that heating to 80 degrees C. may potentiate the toxicity five-fold, so that these beans are more toxic than if eaten raw. In studies of casseroles cooked in slow cookers, internal temperatures often did not exceed 75 degrees C..

All persons, regardless of age or gender, appear to be equally susceptible; the severity is related only to the dose ingested.

No major outbreaks have occurred in the U.S. Outbreaks in the U.K. are far more common, and may be attributed to greater use of dried kidney beans in the U.K., or better physician awareness and reporting.

NOTE: The following procedure has been recommended by the PHLS (Public Health Laboratory Services, Colindale, U.K.) to render kidney, and other, beans safe for consumption:

* Soak in water for at least 5 hours.
* Pour away the water.
* Boil briskly in fresh water for at least 10 minutes.
* Undercooked beans may be more toxic than raw beans.

Sources: FDA (U.S. Food and Drug Administration) Center for Food Safety & Applied Nutrition.
BAD BUG BOOK (Foodborne Pathogenic Microorganisms and Natural Toxins Handbook).

 
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Lefty

Yank
Thanks for the info. For one reason or other I have avoided all kidney beans. I have always found them very dry and they have a pasty texture I dont like. When I cook chili or other dishes with beans I stick to red beans, pintos, pink beans and black beans.
 

joec

New member
Gold Site Supporter
That is probably the one bean we rarely buy dried. When I do dried beans in general I soak them over night changing the water several times in the process. I also usually do them in a pressure cooker preferring them on the softer side than crunchy.
 

FryBoy

New member
From what I've read, some other beans are also problematic, including white kidney beans (a.k.a. Cannelli beans) and lima beans. They have much lower levels of the toxin PHA, but still enough to cause a purge reaction if not cooked properly, eaten raw, or sprouted and used in salads and so forth.

This site has some interesting information: http://davesgarden.com/guides/articles/view/2385/
 

Miniman

Mini man - maxi food
Gold Site Supporter
I was taught that all dried beans should be soaked and boiled for 10 miutes - thats why I usually used tinned, they have been done already.
 

RobsanX

Potato peeler
Super Site Supporter
You guys are bringin me down with all this food poisoning talk! Can we get back to celebrating food instead of fearing it?!
 

QSis

Grill Master
Staff member
Gold Site Supporter
Yeah, I'm with you, Rob!

Okay, all you Henny Pennys stop reading stuff! Or switch over to comic books!

Ostriches .... UNITE!!

Thank you.

Lee
 

FryBoy

New member
Sorry, but I'd rather know so I can avoid problems. To my mind, knowledge is the antidote for fear because what you don't know CAN hurt you.
 

QSis

Grill Master
Staff member
Gold Site Supporter
OTH, what you don't know, you don't fear.

NOW I have a kidney bean phobia!

Lee
 
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