Plum Jam
Plum jam is rich and flavorful, and the perfect way to preserve plums for year-round enjoyment.
Ingredients
- 9 cups chopped plums 3 lbs prepared, from 3 1/2 lbs with pits
- 3 cups sugar 1 1/2 lbs
Instructions
- Place the plums and sugar in a heavy-bottomed jam pot, ensuring that they fill it no more than halfway (the jam will foam up during cooking).
- Turn the heat to high and bring the mixture to a boil, stirring frequently to avoid scorching (8-10 minutes).
- Once the plum/sugar mixture is boiling hard, turn the heat down a bit to medium or medium-high to prevent scorching or overflows. Continue to stir frequently, and cook until the jam reaches gel stage. (That's 220 degrees when tested with an instant-read thermometer). It should take roughly 20 minutes at a boil, or 30 minutes total cook time, but can vary based on the fruit used.
- Once it reaches gel stage, ladle the mixture into prepared jars. Store in the refrigerator for immediate use, or freezer for up to 6 months. Or water bath can for long term storage.
- Optional Canning Instructions: If canning, ladle the finished plum jam into canning jars, leaving 1/4 inch headspace. Cap with 2 part canning lids and process in a water bath canner for 5 minutes (pints & half pints). Adjust canning time to 10 minutes if above 1000 ft in elevation, and to 15 minutes if above 6000 ft.
- Properly canned jam in sealed jars should last for 12-18 months at room temperature in the pantry without losing quality. Once opened, store in the refrigerator and use within a few weeks.
Notes
A note about sugar ~
Feel free to increase or decrease the total amount of sugar in this recipe based on your tastes. I'm using a 2:1 ratio of fruit to sugar by weight. Some recipes use as much as a 1:1 ratio, especially for very tart fruit. I think that's too sweet but to each his own.
Similarly, you can reduce the sugar in this recipe by half, and the jam will still gel. That'd be a 4:1 ratio by weight. The yield will be lower, cook time longer, and the jam tarter, but it's perfectly fine as a low sugar plum jam variation.