Bad company to shop with
lol how many people just keep peanut butter in the cupboard just as it is stored in supermarkets etc non refrigerated? and what a nice spell of warm humid weather we have at the minute, but then again many family kitchens are kept warm even in winter and there is no avoiding humidity in a kitchen....
Well yes and no, it requires particular conditions that are inadvisable for keeping any food really: "The species of molds that combine to form aflatoxin grow in soils when conditions are just right, including when decaying food, plants, hay and grains are piled together to decompose in areas with high moisture and high temperatures" It seems to be a problem in Asia and Africa primarily.
it sure does go off, bigtime, google peanut mould aflatoxins, most interesting case was the experiment to use peanuts as cattle feed in the states.
It says best before 5/4/2019. Also peanut butter doesnt go off..there isn't exactly any water for bacteria to survive...a bit like honey!