It depends. Peanut butter generally doesn’t need to refrigerated- BUT, peanut butter generally only keeps a few months once opened and out of the fridge. It is especially true if you live in a hot climate where separation and spoilage can occur more rapidly.
Peanut butter can be kept safe and from separating for half a year or more in the fridge, but in cold climates you can often get similar longevity without placing it in the fridge. The peanut butter, ingredients, and production methods also impact this, peanut butter is inherently a fairly shelf stable food but “less processed” foods often do not keep as long or remain as safe as their counterparts over time without precautions.
Likewise, it can depend on your practices. If you are spreading peanut butter on things and placing the knife back in the jar with particulates or contaminants on it, you can introduce material to the peanut butter that isn’t shelf stable, and/or microorganisms that without refrigeration can cause..
.. spoilage or other potential issues and hazards. Of course it is generally easier to spread room temperature or warm peanut butter than cold peanut butter out of the fridge- so preference for consistency etc. play a part. All in all any individual storage of peanut butter is just that- individual. Based on circumstances like climate and how long a jar of peanut butter lasts you or your preferences. If you plan to keep peanut butter longer than a few months you generally should refrigerate it at least once it has been on the shelf a few months.
Peanut butter can be kept safe and from separating for half a year or more in the fridge, but in cold climates you can often get similar longevity without placing it in the fridge. The peanut butter, ingredients, and production methods also impact this, peanut butter is inherently a fairly shelf stable food but “less processed” foods often do not keep as long or remain as safe as their counterparts over time without precautions.
Likewise, it can depend on your practices. If you are spreading peanut butter on things and placing the knife back in the jar with particulates or contaminants on it, you can introduce material to the peanut butter that isn’t shelf stable, and/or microorganisms that without refrigeration can cause..