Usually I buy fresh-ground peanut butter in single-sandwich serving sizes, since I only eat a PB&J sandwich once or twice a month. But being two lazy to drive to Harry's Farmer Market, I went with Smucker's Natural Peanut Butter today.
My question is: how long will the jar last when stored in the fridge after opening? Its only two ingredients are peanuts and a bit of salt, so it's the type of natural peanut butter with no sugar, where the oil separates out so you need to stir it. And you refrigerate it after opening.
But how long will it last before going bad? And how can I tell when it's gone bad?