Quick Answer
To successfully can raspberry jam, use a tested recipe, follow safe canning procedures, and ensure your jars are properly sterilized and sealed.
Preparing the Recipe and Equipment
When canning raspberry jam, it’s essential to use a tested recipe from a reliable source, such as the USDA’s Complete Guide to Home Canning. This ensures the jam is acidic enough to prevent bacterial growth and spoilage. For this recipe, use 3 cups of fresh raspberries, 1 cup of granulated sugar, and 1 tablespoon of lemon juice. Sterilize your equipment, jars, and lids by washing them in hot soapy water and then submerging them in a pot of boiling water for 10-15 minutes.
Canning the Jam
To can the jam, prepare your jars by filling them with the hot jam mixture, leaving about 1/4 inch of headspace. Remove any air bubbles by running a non-metallic utensil around the inside of the jar. Wipe the rims with a clean, damp cloth and apply the sterilized lids and rings. Process the jars in a boiling water bath for 5 minutes, adjusting for altitude as necessary. Let the jars cool, undisturbed, for 12-24 hours before checking the seals.
Storage and Safety
Store the sealed jars in a cool, dark place for up to 12 months. Before consuming, always check the seal by pressing on the top of the lid; if it doesn’t move and the lid is concave, the jar is sealed properly. Never store jars near direct sunlight, heat sources, or moisture, as this can compromise the seal and lead to spoilage. If you notice any signs of spoilage, such as mold, swelling, or leakage, discard the jar immediately and re-can the jam following safe procedures.
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