When you purchase natural peanut butter, there is a layer of oil at the top of the jar. Is this layer supposed to be mixed in (as I know that oil separates from a product after a certain amount of time), or is it supposed to be drained off? I want to keep the content of the peanut butter as consistent with the nutritional information on the side. I'm trying to keep a precise fat intake so I can keep my 40/40/20 macro accurate. Thanks!