Question: A friend of mine always stores her peanut butter in the fridge after opening it. Is that necessary?
Answer: No — it’s not necessary to refrigerate an opened jar of commercially manufactured peanut butter, says the National Peanut Board.
An opened jar of processed peanut butter will usually keep well for about 3 months when stored in a dark cupboard at normal room temperature. And the major benefit of pantry storage, of course, is that it allows the peanut butter to spread more easily.
That said, if you’re not able to finish off the entire jar of peanut butter within a few months — or if your pantry tends to get extremely hot and humid — storing the opened jar in the refrigerator can help keep the peanut butter at optimum freshness longer. Once refrigerated, it will generally remain at good quality for an additional 3 to 4 months.
Should You Keep Potatoes in the Fridge?
Do You Have to Refrigerate Opened Bottles of Mustard and Ketchup?
Does Pumpkin Pie Have to Be Refrigerated?