In my introductory column, I teased a jam article, but as soon as I sat down to write, I was overwhelmed. Should I cover traditional jams, low-sugar jams, or freezer jams? Could one article include the safe use of boiling water canners and the science of sugar, pectin, and acid?
In the end, I decided that freezer jams would be the perfect subject for the first article.
Freezer jams get their name for two reasons. First, they are not shelf-stable and need to be stored in the freezer until you plan on eating them. Unopened, they can be stored in your freezer for up to a year without impacting the quality. Once opened, they must be stored in the refrigerator, usually for up to three weeks.
Second, freezer jams don’t require cooking the fruit, saving you from standing over a bubbling pot of fruit in the summer heat. The resulting jam retains more fresh fruit flavor than your typical store-bought jar. However, freezer jam does require a special ingredient: pectin.
Pectin is the key to making a spreadable jam and not a sticky syrup. Fruit naturally contains varying levels of pectin depending on the type of fruit, the ripeness, and the part of the fruit. In a traditional jam recipe, heat and acid help the fruit release pectin. Sugar attracts water away from the pectin, allowing the pectin to form a stronger bond with itself and create that jam consistency. Since freezer jams are not heated, adding pectin as a separate ingredient is necessary.
While pectin occurs naturally, it is also commercially available and is used to reduce the cooking time of traditional jams and increase the odds a jam will set. Special low- or no-sugar pectin uses calcium to create the bond instead of relying on sugar, allowing us to use less sugar or sugar substitutes. Locally, Wilco and Fred Meyer carry different brands of both the low- or no-sugar and classic pectins. A favorite pectin for low- and no-sugar recipes, Pomona’s Universal Pectin, is easiest to purchase online.
Many types of fruit work well for freezer jam, but I’m particular to peaches and blackberries, which are in season now. The pectin you use will have its own set of instructions and measurements, so be sure to follow the guidelines specific to that brand. If you use Ball’s low- or no-sugar pectin, you could follow either of these:
https://www.ballmasonjars.com/blog?cid=peach-freezer-jam
https://www.ballmasonjars.com/blog?cid=blackberry-freezer-jam
You don’t have to limit yourself to fresh fruit. Frozen fruit, once defrosted, can be used as well. I currently have too many blueberries in my freezer and am thinking about flavor combinations for a future jam. It’s safe to add small amounts of dried herbs, zests, or flavorings, such as vanilla paste, to jam recipes. This opens the door for culinary creativity. To infuse flavoring into uncooked freezer jam, I’d recommend using a baking technique of rubbing the dried herb or zest into the sugar with your hands before adding the sugar to the fruit. Orange zest would go particularly well with blueberries, or for a more unusual combination, a small amount of lavender.
To ensure jam success, do not double or triple the recipe. Jams often do not set properly when recipes are increased. Wash your half-pint or pint jars in hot, soapy water before filling and be sure to leave 1/2 inch of headspace to allow for expansion in the freezer.
