Natural Pectin Content of Berry and Tree Fruits

Preserve making with high-low pectin fruit can use the loose jam approach or making set jams. Making a set jam will require naturally high levels of pectin or some way of compensating when preserving fruits with medium to low pectin content.

Fruits with High Pectin Content

Fruits with naturally high pectin content include citrus fruit such as limes and lemons, berry fruit such as cranberries, loganberries, redcurrants and blackcurrants, and tree top fruit such as quinces and apples. If the fruits are in top condition, then granulated sugar or fruit juices can be used in making a set jam or jelly.

Pectin content may be reduced where the soft berry fruits, tree fruits and citrus fruit show signs of fungal infection and disease. Professor Stefan Buczacki in Plant Problems Prevention and Control (David & Charles, 2000) writes “Pectin is an important substance in ‘gluing’ plant cells together (it’s what makes jam set), and so fungi that can break it down produce soft rot and decay in plant tissues.”

Fruits with Low Pectin Content

Fruits with naturally low pectin content include tree fruits such as figs, cherries, nectarines, pears and soft berry fruit such as late varieties of blackberries, strawberries and elderberries. Edible stems of forced rhubarb and early and maincrop varieties of rhubarb, frequently treated like a fruit in preserves, are naturally low in pectin content.

Making a set jam with lower pectin content in fruit requires preserving sugar or jam sugar for a guaranteed high pectin content and good set to the fruit preserve. For best results, half the recipe’s amount of preserving sugar or jam sugar can be added to fruit with low pectin content with freshly squeezed lime juice and then mashed to allow the pectin content of the preserving or jam sugar and the limes to infuse into the low pectin fruit. Maggie Mayhew takes this approach in her ‘Blueberry and Lime Jam’ published in her Jams, Jellies & Marmalades Step-by-Step Recipes for Home Preserving (Apple Press, 2008).

Fruits with Medium Pectin Content

Prepared pectin has been used in making preserves commercially and at home for at least 80 years. In Economical Cookery (Morrison & Gibb, 1930), the anonymous writer reports on the commercial availability of pectin for making strawberry jam “Pure pectin is now available, and sold by two firms of repute. One is in powdered form and the other a semi-liquid.”

Fruit gardeners keen on making preserves with their blackberries or raspberries, which have naturally moderate or medium pectin content, will find that preserving sugar or jam sugar can be bought with added pectin.

Stone fruit such as peaches, plums and apricots have moderate levels of natural pectin. Making a set jam with raspberries, bilberries, early varieties of blackberries, blackberry hybrids and other bramble fruit will require those making preserves to combine the fruits with other fruits with high pectin content, add pectin or use jam or preserving sugar.