- How long does an unopened jar of plum jam last? The precise answer depends to a large extent on storage conditions -to maximize shelf life, store in a cool, dry area.
How long does an unopened jar of plum jam last at room temperature? Properly stored, an unopened jar of plum jam will generally stay at best quality for about 2 years.
Is unopened plum jam safe to use after the expiration date on the jar? Yes, provided it is properly stored and the jar is undamaged - commercially packaged plum jam will typically carry a Best By," "Best if Used By," Best Before, or "Best When Used By" date but this is not a safety date, it is the manufacturer's estimate of how long the plum jam will remain at peak quality.
Storage time shown is for best quality only - after that, the plum jam's texture, color or flavor may change, but in most cases, it will still be safe to consume if it has been stored properly, the jar is undamaged, and there are no signs of spoilage (see below).
How can you tell if plum jam is bad or spoiled? The best way is to smell and look at the plum jam: if the jam develops an off odor, flavor or appearance, or if mold appears, it should be discarded.
Sources: For details about data sources used for food storage information, please click here