Ask Extension Database, NDSU Extension Service Ask Extension for answers to commonly asked questions. University of Wisconsin Many fruits you use for making jam and jelly mature at about the same time. Because of this, you may find it difficult to make as much jam and jelly as you would like, while the fruits are in season. You can freeze many of these fruits in summer and make them into jam during fall and winter.
Accurate measurements are important when making jam.
For this reason, you should pack the measured amount and then mark the measure on the airtight container. Do not add any sugar to fruit you freeze to make jam or jelly. When you make jam from frozen fruit, thaw the fruit in the refrigerator until only a few ice crystals remain. You will save freezer space if you make juice before freezing, instead of making it from frozen fruit. Take time to boil the fruit to extract the pectin and the juice.