“When you open a jar of jam and let it sit for some time without eating it, mold can form on the surface. While the taste may still be fine, there’s nothing like enjoying mold-free jam. Follow these tips to help prevent mold and enjoy your jam without worries. “
If you’ve opened a jar of jam and haven’t even started eating it, it’s likely that mold will develop. You can still eat the jam even if there’s mold, but it’s essential to remove it for hygiene reasons. Adding a thin layer of sugar to your jam after opening the jar is sufficient to prevent such spoilage. Note that the mold’s origin is the improper sterilization of the jars and their lids.
Recommendations for preventing mold on homemade jam:
The first thing to do is to add an equivalent amount of sugar, about 70 to 80% of the weight of the ready-to-cook fruits. For example, if you have 2 kg of rhubarb, add 1.4 to 1.6 kg of sugar. This is the ideal trick to prevent mold. However, be cautious about this sugar addition. Avoid using sugar with pectin and opt for crystallized sugar, even though it requires about 40 minutes of cooking, depending on the fruits. Also, use only the same type of jars as Bormioli, a well-known Italian brand with new lids. Do not choose jars with suction lids! Next, fill your containers to the brim with very hot jam and invert the lids to add strong alcohol like grappa, an Italian grape marc brandy, or rum. Finally, remove the alcohol from the lids without wiping them, close the jars, and invert them during the entire cooling process.