The Oreo Balls will keep fresh in the refrigerator for up to 1 to 2 weeks.
But the Oreo Balls will still be good to eat when kept in the refrigerator for up to 1 month before going stale or bad.
Usually I never keep the Oreo Balls in my refrigerator longer than a week because me and my family tend to eat them up way before then.
After you make the Oreo Balls the balls will create what's known as truffles when put in the refrigerator for 1 hour and those truffles will keep the Oreo Balls airtight.