Is it safe to cook beans in a slow cooker? Not an issue I face every day, but when I do, I want the right answer.
If you are like me, you skim a lot of headlines from various sources. Then you carry bits of information around in your head until your forget them or you find a way to put them into context.
Weeks ago, I saw something about the dangers of cooking beans in a slow cooker. With no idea where information came from, what the particulars were, or how reliable the source was, the words “danger“, “beans“, and “slow cooker” stayed with me.
The only way for me to ever cook another bean in a slow cooker without worrying that I would poison someone was to find out the facts. Here is what I found out:
Kidney beans should not be cooked from raw in a slow cooker.
If you care about the scientific reason – it’s that the beans contain a protein, called phytohaemagglutinin, which is toxic. Even just a few raw or undercooked beans can make you quite ill. Cooking the beans properly destroys the toxin. Soaking and then boiling the beans for at least 10 minutes (some authorities – including the FDA’s Bad Bug Book (Seriously – that’s the name of the publication. Don’t you love it!) – suggest boiling for at least 30 minutes) will eliminate the toxin. Slow cookers may not reach a high enough temperature and hold it for long enough to kill the toxin. If you have a slow cooker recipe that calls for kidney beans, either cook them first or use canned beans, because they are pre-cooked before canning.
This precaution is most important for red kidney beans, but also applies to white ones. The latter are sometimes called cannellini beans. Red kidney beans contain about 3 times as much of the toxic agent as the white ones, but white kidney beans can also cause illness if not fully cooked. I’ve also seen cautions about raw or undercooked soy beans (which contain a different toxin, called a trypsin inhibitor, which is also destroyed with the same type of proper boiling/cooking), but I rarely see recipes that call for cooking raw soy beans.
Now I can comfortably go back to cooking chili, enjoying fully cooked kidney beans in salad, and using my slow cooker again for bean soups and stews.
Have you ever read, heard, or half-remembered a food safety tip that you’d like to check out? Leave a comment and let’s research it.