Homemade blueberry jam
7 cups sugar
8 cups blueberries
1 package fruit pectin
1 tablespoon butter
3 tablespoons lemon juice
5 pint-sized jars Jar rings and lids
Dry measuring cup
Liquid measuring cup
Large pot ladle
2 large bowls
1. Sterilize jars, rings, and lids by placing them in a large stock pot of water and bringing to a rolling boil for 10 minutes.
2. Measure out 7 cups of sugar using a dry measuring cup and place in a separate bowl. *Reducing the amount of sugar will result in jam failure.
3. Thoroughly wash blueberries and remove any debris such as leaves, stems, or thorns. Using a potato masher (or hands), crush berries, add lemon juice and stir until combined. Using a dry measuring cup, measure out 5 cups of crushed berries and add to a large saucepan.
4. Add 1 package of fruit pectin to prepared fruit in pot. Stir in butter to reduce foaming while cooking.
5. Bring mixture to a roiling boil over high heat, stirring constantly. (A roiling boil is one that does not stop bubbling when stirred.)
6. Add sugar to mixture and return to a roiling boil and cook for exactly 1 minute. Remove mixture from heat, and if necessary, remove any foam with a large spoon.
7. Using a ladle, immediately fill the prepared jars, filling each 1/4 inch from the top. Wipe away any excess from the threads. Place top on jar, and firmly screw the jar ring onto the jar.
8. Place jars upside down on a towel and allow to sit for 5–10 minutes. Flip over and allow to cool completely. As jars cool, a popping sound will be heard, signaling that the jar lid has properly sealed. Store prepared jams in a cool, dry place.