Sometimes, when I'm eating walnuts, I'll find one with some dark spots on the kern surface, as shown in the photograph below. I normally prefer to err on the side of caution (I think I read somewhere once about them being some sort of mold) and throw it away. Just in case I'm throwing away some fine and expensive delicious walnuts, I'd like to ask if somebody know what these spots are, and if they are safe to eat or not.
Thaks for your time, and sorry if it's a silly question.
