Did you know beans can ferment if soaked too long?
I had a bag of beans that I split in half for different recipes. I cooked one but did not have time to get to the other that same day, so I just changed the water and let the beans soak another night. They smelled "funny" when I rinsed them and got ready to cook them. As they cooked my son stated that "whatever is in the kitchen smells bad!" I agreed. After a short search online, I learned that beans can ferment if left to soak too long. I think these sure did.