Packed with berry flavor, this jam is tasty enough to eat off the spoon. Pectin is necessary to make a properly thickened jam, but rather than go for the store-bought kind we used apple peel for an all-natural spread.
Special equipment: We’re assuming that you already have basic tools lying around (like cutting boards, bowls, and measuring cups), so here’s the special equipment you’ll need for canning:
• Boiling water canner or 15- to 20-quart pot with a tightfitting lid
• Canning rack that fits inside the boiling water canner or 15- to 20-quart pot
What to buy: Bottled lemon juice may sound counterintuitive, but it helps ensure a uniform acidity level, which is vital to proper canning.
General canning tips: Before you turn on the heat, be sure to do the following: Read the recipe through, gather all necessary equipment, and check that you have the right amount of each ingredient on hand.
Give all your equipment a once-over: Examine your canning jars for nicks, cracks, uneven rims, or sharp edges that may prevent sealing or cause breakage; check that the lids have no dents and that the sealing compound is even and complete; and check that the bands fit properly.
Finally, have your jars, lids, and bands already sanitized before you start, and prepare only enough for one canner load at a time.
Blueberry jam – specific tips: Select fresh berries at their peak, and use firm, uniform-size produce free of any cracks, spots, or growths.
The jam is ready when it passes the plate test: Once you draw your finger through the cooled jam (see below), it should hold together on the plate without being runny. Don’t wait until it is a solid, unmovable mass or it will be overcooked and caramelized.
For the jam:
For processing the packed jars: