Who doesn’t love the humble, delicious red kidney bean? The rosy legume is a pantry staple, used in soups, spicy slow-cooker chili, and salads. It is hearty, flavor-rich, and inexpensive, especially when purchased dry. If you’ve never prepared kidney beans from their dry state, cooking them might seem as simple as popping them on the stovetop (or in a pressure cooker) with water to boil. Certain beans can be slow-cooked from their dry state, including black beans. However, this is not the case for red kidney beans. In fact, cooking dry red kidney beans can actually be quite dangerous, even causing serious illness in some cases. So why is this?
Well, red kidney beans contain high levels of phytohaemagglutinin, or PHA, a toxin that can cause an illness known as red kidney bean poisoning. In order to prevent this poisoning and reduce PHA levels, it’s important to soak your beans prior to cooking and boil for at least ten minutes if you use a low-temperature cooking method. Soaking your beans for at least 5 hours will help eliminate PHA, and boiling at a high temperature for at least 10 minutes will ensure that the PHA is no longer active.
No beans about safety
It’s all well and good to note the importance of soaking and boiling your beans, but there are a few pointers to keep in mind in order to ensure that your beans are prepared properly. In terms of soaking, you’ll want to keep your beans submerged in a fresh batch of water for at least five hours to overnight. This will allow your beans to be more fully hydrated and make cooking your beans more efficient so that you don’t end up eating dry, crunchy, dangerous beans. Beyond safety, which, of course, comes first, soaking beans will help to ensure your cooked beans have the best possible texture. Boiling your beans at a high temperature will eliminate PHAs, so long as you’ve soaked and cooked your beans. Boil them at a temperature above 212 degrees Fahrenheit for over ten minutes; they should be safe to eat.
The second point, cooking to the correct temperature, is especially important to consider if you are preparing your beans using a low-temperature method, such as pressure cooking. Often, beans cooked in a pressure cooker only reach 167 degrees Fahrenheit, meaning they aren’t cooked to a high enough heat to fully destroy the PHA toxins. This guidance only applies to dry red kidney beans. Canned red kidney beans have already been prepared in such a way as to eliminate PHAs. So, next time you’re cooking from dry, remember first to soak and boil.
