Updated: Oct 23, 2020
This recipe calls for just four ingredients. It's more of a formula than recipe, and will help you make all of your own favorite fruits into preserves and jams. No pectin necessary, and no need to worry about getting special additives to add for your jam. The same effect can be created with the proper time and care, while keeping your jam all-natural, and most importantly-simple.
3 pounds fresh berries
4 1/12 cups sugar
4 1/2 teaspoons lemon juice (from 1/2 of a lemon)
Pinch of coarse salt
1. Place a few small plates in the freezer. Stir berries, sugar, lemon juice, and salt in a large, heavy stockpot. Bring to a boil, stirring to dissolve sugar and mashing lightly with a potato masher. Skim foam from surface. Cook, stirring more frequently as jam thickens, until it has the consistency of very loose jelly, 8 to 9 minutes. Remove from heat.
2. Remove a plate from freezer; drop a spoonful of jam on it. Return to freezer for 1 to 2 minutes; nudge edge of jam with a finger. It should hold its shape. If jam is too thin and spreads, return it to a boil, testing every minute, until done.
3. Strain about half of the jam; discard seeds. Return strained jam to pot. Return to a boil. Remove from heat. Spoon hot jam into hot sterilized jars; cover immediately with sterilized lids,
4. Submerge filled jars in pot of boiling water, making certain that all jars are completely covered. Cover pot and allow low boil for 10 minutes. Remove jars and let cool, You should hear a clicking sound as each jar vacuum seals.
5. Store jars in a dry, cool location. Preserved jam can last up to 18 months.