Wednesday, November 2, 2011

Attack of the Killer Kidney Beans

Ok, I've watched too many low-budget horror movies lately.

If the Halloween zombie horses didn't get you, please tune in for the following announcement.

Beware the Red Kidney Beans

Tis the season for warm soup, stew, and chili.  Prepare these comfort foods with caution if they call for red kidney beans.  Canned, processed kidney beans are relatively gentle, peace loving legumes.  But dried red kidney beans are armed and dangerous.  They must be frisked at the kitchen door and rendered harmless before you invite them to dinner.

I attended a Halloween party last weekend that included a popular Fall culinary event:  The Chili Cookoff.

The buffet table was lined with 20 or more crock-pots containing a variety of chili concoctions.  I sampled three of the chili dishes.  A few hours later I became ill - violently ill - like I've never experienced before.

I suspect I fell victim to kidney bean poisoning.

Dried red kidney beans contain a toxin called Phytohaemagglutinin.  This toxin is present in many types of beans, but the red kidney bean wins the prize for packing the highest concentration. It only takes a few unfit beans to make a person very sick.

One of the most sinister methods of cooking dried red kidney beans is to slow-cook them in a crock-pot (or slow-simmer on the stove).  The temperature may not get high enough to kill the toxic agent.  In fact, slow cooking may increase the potency of the toxin.

The raw beans must be boiled for at least 10 minutes

If you ingest toxic kidney beans, your tummy will expel the ghastly substance as quickly and thoroughly as possible.

The process is absolutely miserable!

But good for a rapid 2 pound weight loss.

Suggested steps to prepare raw beans before using them in a recipe or crock-pot:
  1. Soak raw beans for at least 5 hours.
  2. Discard the soaking water.
  3. Place beans in clean water; bring to a boil and continue boiling for 10 minutes, stirring occasionally.
I'm not a scientist, doctor, toxicologist; nor am I a professional chef.  So don't take my word for it.  Research multiple online sources (not all Internet cooking advice is valid) and be careful when cooking with raw beans.

Interesting resources:

Bad Bug Book: Phytohaemagglutinin (Kidney Bean Lectin)  from U.S. Food and Drug Administration

Beans! Beans! The Poisonous Fruit!  from

Red Kidney Bean Poisoning  from

P.S.  Horse Owners:  Beware the White Kidney Beans too.

Abstract from

Thirty-four mixed breed horses from two separate farms showed signs of abdominal discomfort, pyrexia and dehydration after being exposed to a new batch of 14% complete horse feed. A new batch of cattle feed from the same manufacturer resulted in dairy cows showing depression, a drop in milk production and diarrhoea. Examination of both diets revealed the presence of white kidney beans (Phaseolus vulgaris). Inclusion of raw beans of this genus in animal feeds is to be avoided.


  1. One of the Dick Francis mysteries is about poisoning people with raw kidney beans. I had no idea until I read that how toxic they are. I stick to canned. I hope you are feeling better and glad you got rid of them fast.

  2. Barbara, I like mysteries, but I've not read any Dick Francis books yet. I will have to start with the kidney bean mystery. Do you know the title? I'll have empathy for the victims. Feeling much better, thanks.

  3. Wow, my Dad used to grow his own kidney beans and then make baked beans with them. Luckily we never got sick but I will definitely always use canned from now on.

  4. RMY, that's probably the safest bet, unless you want to soak and boil. It'll be a long time before I can even look at a bowl of chili. I don't ever want to eat it unless it is commercially prepared or I make it myself at home or if I know the cook followed the right precautions.

    How are you? How is Rosie? Are you riding and driving?

  5. And I thought flatulence was the only byproduct of eating beans!
    You must read Dick Frances! I love his books - but haven't read the bean one. I'll have to check it out!

  6. Dreaming, tee hee, yeah, I think the flatulence side-effect is much better known. Not many people know about the bean poison because it doesn't happen a lot. I read about it a year ago, but it didn't cross my mind at the chili dinner. But now I'll think of it every time I see a bowl of chili.

  7. The Francis mystery is Dead Heat.
    It is by Dick & Felix Francis and it is one of his later ones where all the action is not on the track. His early ones are more horsey but once you read one you have to read them all. Enjoy!

  8. And just to stick up for SW cooking - chile is NOT supposed to have kidney beans in it anyway. Pinto beans, black beans, not kidney beans. That is what we used to call Irish Chile.

  9. Thanks for the book title Barbara. I'll read it. I wish the chili I'd eaten last weekend followed that SW rule. My husband suggested I start with some "texas chili" (no beans whatsoever). I just need time for the memory to fade. :-)

  10. ... adds this as another thing I learned today.

    Glad you are feeling better. Did you let it 'run it's course' or head to the hospital?

  11. Thanks Jeni. It ran its course fairly quickly once I "tossed" the chili. I felt wimpy the next day, but fine by day 2.

  12. Oh my goodness! I'm making chili tomorrow, but I use canned beans. Now I can tell people I use canned beans for safety instead of the real reason - I'm lazy!

  13. Wow, glad you're okay. Another good reason why I don't like to cook much.

    Thanks for the informative post, I had no idea.

  14. Wow, who knew? Not me. Glad you are feeling better!

  15. Terry, hope your chile was delicious. Canned beans are great.

    Thanks Gray Horse & aurora.

  16. Wow! I am so glad you are feeling better. That sounds awful. I never knew that at all and we eat kidney beans like mad here. I guess we always use the canned kind - lazy short cut that might have saved us some misery!

  17. Yikes - what a way to cleanse! hope you are on the mend now and Thanks for the heads up!

    When I had babies I had a special sweet feed blend to grow brains and body - I always made sure that the feed mill used a special mixer for horses only - if any cattle feed was mixed in there it would be toxic to horses - as with everything we cant assume ;)