Fill the jam into jars to the bottom because when the jars are closed, very little air remains—always fill the jam with hot jam, never let it cool after boiling. And when filling the jam, it is certain that there are no air pockets or unfilled corners of the jar. If you use more than 65% of the final weight in sugar, then that jam will be preserved longer than jam with less than 65%—at least 6 months for years, or even longer. If you use metal lids in jars, be sure they have been covered with plastic. Although you want to preserve your heavy labor (and the attractive appearance of the jam), then store the jam in a dark, cool place after closing, and when opening it, the best practice is to place the jars in the refrigerator until they are consumed, up to a month. And although it is important to seal the jars immediately after filling to ensure they remain sterile, however, you should then remove the jars to cool them completely before labeling and storing them to avoid the risk of burns.
