If you don't boil the beans for at least 5-10 minutes BEFORE you fully cook them, you run the risk of aflatoxin poisoning, especially from red (kidney type). Recommended cooking method for most beans is: into pan of cold water, no salt as this toughens skins, bring to boil, skimming off scummy bits and boil hard for 5-10 minutes. Drain, rinse, then put into clean water, bring back to the boil and cook until tender (the pack will give you a rough guide, but cooking times depend on how old the beans are and how the have been stored). This method not only kills off the aflatoxins, but also removes a lot of the fart potential. Tried, tested and effective!