Red jam refers to a mixed fruit jam which is necessarily red in color, usually owing to presence of red currants, apricots, berries or red plums. The fruits are cut into small pieces or crushed and cooked in sugar syrup. The preparation of red jam traditionally involves the use of pectin as a gelling agent, although sugar or honey may be used as well. The fruits are heated with water and sugar to activate the pectin in the fruit. The mixture is then put into containers. You may also take advantage of fresh plums in season to make delicious plum jam at home. Place chopped fruits, water, and lemon juice in a large non-aluminum stockpot. Stirring often, bring to a boil over medium-high heat. Cover, reduce heat to low, and simmer 10 minutes, stirring occasionally, until fruit is soft. Stir in sugar. Return heat to high and bring back to a rolling boil while constantly stirring. Add pectin and return to a boil while stirring. Continue to stir and boil for 1 minute, then remove from heat. Let rest for 1 minute and the delicious red jam is ready.