Jam setting - Tips for getting jam to set

To set well, jam needs the right balance of pectin and acid. Lemons provide the acid, but different types of fruit have various levels of pectin.

Pectin rich fruits include apples, gooseberries, blackcurrants, redcurrants and damsons. Combine fruits with differing pectin contents, such as strawberries (low in pectin) and redcurrants, or apples and blackberries (also low).

Test the jam for setting point when it reaches 105°C/220°F (use a sugar thermometer to test the temperature). Dip a wooden spoon into the jam, lift it out horizontally and keep it in this position to cool. Then tilt the spoon and let the jam fall off it. If small drops run together on the edge of the spoon to form larger drops that then fall cleanly off the spoon, the jam has boiled long enough.

Or, drop a small spoonful of the hot jam onto a cold plate. If it forms a skin on the surface as it cools, which wrinkles when you press it, the jam is at setting point and is ready to pot.

If the potted jam is runny and won't set, don't reboil it - you will only ruin its flavour. Dissolve gelatine in warm water, warm the jam - simply so that you can mix it with the warm gelatine - and stir it into the gelatine solution. (Use 5-6 teaspoons of gelatine for 2½-31b/1.1-1.4kg of jam.) Pot it again and refrigerate when cool. Use it within a few weeks or it may become mouldy.