Pectin is a naturally occurring carbohydrate found mostly in the skin and core of fruit, when combined with acid and sugar it forms a gel, the essential process for setting jam.

Different types of fruit have different levels of pectin content, and it is at it's highest levels in slightly under-ripe fruit.

When making jam or jelly with a fruit high in pectin it will set easily.

Low pectin fruit can still be made to set, but will need help in one of the following ways:

• Combining with other high pectin fruits (for example Rhubarb and Orange Jam)

• Adding pectin stock (home made from apples or gooseberries), or commercial pectin.

• Using jam sugar with added pectin (as in this Raspberry Jam recipe)

• Adding lemon juice to the fruit, the acid helps extract the pectin.

The list below is intended as a guide, bear in mind that most recipes will say if you need to add extra pectin.

Links are to recipes containing that fruit.