Pectin

Pectin is a natural fibre found in plant cell walls and most concentrated in the skin of fruits. It is water-soluble and binds with sugar and fruit acid to form a gel. Adding pectin when making jam or jelly also shortens or eliminates the cooking time, resulting in a fresher fruit flavour.

Using pectin, rather than the long boil method, has the additional benefit of yielding up to 50% more jam or jelly from a given amount of fruit. Wine jellies, bottled juice jellies and no-cook jams can only be made by adding pectin. The amount of pectin varies from fruit to fruit & depends on the stage of ripeness and the growing season weather. The riper the fruit, the less pectin.

• High pectin / high acid fruits
  Crabapples, sour apples, currants, gooseberries, cranberries, lemons, limes, grapes, blackberries, Seville oranges (sweet oranges are low in acid)
• Low pectin / low acid fruits
  Strawberries, peaches, blueberries, sweet cherries, raspberries, pears, elderberries, overripe fruit.

Acid

Acid in fruit is required to form the gel. In some jam recipes additional acid is required for a proper set. Lemon juice is an example of an added acid.

Low acid will affect gel set and the fruit may float to the top, instead of staying immersed.

The Importance of Good Fruit

Use firm ripe fruit without mould or bruises. The better the fruit, the better the jam. Overripe fruit has lower levels of acid and pectin and could result in a soft set. Underripe fruit has reduced juice and will result in poor flavour.