The Best Blueberry Jam
10 cups Jersey Fresh blueberries, 6 cups mashed
8 TB pectin (we used Ball RealFruit Classic Pectin)
4 ½ cups sugar, divided
¼ cup lemon juice
½ cup water
10, 8 oz jars with lids and rings (we canned 7 and refrigerated 3)
Canning rack and 1 huge pot for canning, or canner
Pie plate for mashing berries
Bowl to store prepared fruit before cooking
1 large pot for jam, about 16-20 quart
Magnetic Lid Lifter
Kettle, if necessary
Large spoons and ladle
45m prep time / 45-55m cook time
2. Rinse the blueberries.
3. Sanitize the jars and lids: put rack and jars in the pot, fill with hot water to cover with 1 inch. Bring to a boil and boil for 10 minutes. Leave jars in hot water until ready to fill. Prior to filling, remove carefully and dry and place right side up on kitchen towel. Leave hot water in pot, for canning your jars. Place lids in a pot of simmering water for 10 minutes before filling jars.
4. Mix pectin with ¼ cup sugar.
5. Place the blueberries one layer at a time in a pie plate, remove stems or bruised berries. Crush and add to a bowl. Repeat for all berries.
6. Make the jam: place the crushed berries in a large pot and stir in the pectin / sugar mixture, lemon juice and water. Over medium to high heat (stirring often to prevent burning), bring to a boil (the kind that cannot be stirred away). Add the rest of the sugar, and then bring it back to a boil and boil hard for 1 minute.
7. Skim foam off, if necessary.
8. Fill jars: place funnel into jar. Using a ladle, carefully pour jam into jar leaving ¼” head space. Remove air bubbles with a plastic spatula, wipe the rim. Using a magnetic lid lifter, place a lid on the jar. Place rim on top and adjust to fingertip tight. Repeat for all jars.
9. Process the jars for long time storage: using the jar grabber carefully place filled jars in the large pot of hot water with rack ensuring jars are covered by 1 to 2 inches of water (you can add hot water from kettle to get to proper level). Place lid on pot. Bring water to gentle, steady boil. Boil jars for 10 minutes. Turn off heat, remove lid and let jars stand for 5 minutes.
10. Cool the jars: carefully remove the jars using the jar grabber and place on a kitchen towel or cooling rack. Let cool for 24 hours. After 24 hours, check lids for seal (lid should not flex up and down when center is pressed).
11. Label jars with 'Jersey Fresh Blueberry Jam' & date. Store in cool, dry place.
NOTE: You can simply jar, cool and refrigerate the amount you plan to use right away. Canned jars are best used within 6 months.