Wash the fruit and drain.
Pit fruits with stones. Cut large fruits into pieces or in half as for apricots.
Weigh the fruit and mix with the amount of sugar indicated in the recipe.
Mix in the cooking pot or in a glass bowl.
Mix well to moisten the sugar with the fruit juice.
Strain and leave to macerate until most of the sugar has liquefied. The sugar becomes like syrup.
Leave to macerate for 12 hours in a cool place. I usually leave them for 2 to 4 hours at room temperature.
The next day, transfer to a large, wide pot and place over high heat.
Cook for 15 to 20 minutes from boiling. Stir often enough to prevent the jam from sticking to the bottom of the bowl. If using a thermometer, remove from heat at 104/105°C (219/221°F).
Lower the heat towards the last 5 minutes of cooking.
Skim with a skimmer.
Check cooking:1. Pour a little jam onto a frozen spoon or plate. Wait a few seconds and run your finger along the line. The line should not close, indicating that the jam is fine.2. Pour a teaspoon of jam onto a cold plate. The jam should stay in place or run slightly if you tilt the plate.3. Use a sugar thermometer. Remove jam from heat to 104/105°C (219/221°F). The jam thickens as it cools. Pour the hot jam into the sterilized jars.
Use a funnel to pour the jam without dirtying the jars.
Fill to 0.5 cm (0.2 inches) from the top.
Replace the lids and screw on tightly.
Turn the jars upside down onto a towel.
After 2 h, tighten the lids.
Allow to cool completely before inverting and storing in a dry, dark place. The closet is ideal.
The jams will keep for a year or more.