I have something of a glut of citrus fruit at the moment, courtesy of my weekly organic box from Abel and Cole, so my thoughts turned to marmalade. Although traditionally made with the sour Seville orange, it is also possible to use sweet oranges, especially if you up the acid and pectin content by adding lemons to the mix.
Marmalade is nothing more than orange jam, but the traditional recipe, originating in Dundee, requires two particular things – the afore-mentioned Seville orange, and finely or thickly sliced orange zest. The word marmalade comes from the portguese marmelada, which originally described a quince jam something like quince cheese or membrillo. Like quinces, citrus fruits are rich in pectin, the substance that sets jams and jellies into that particular firm and quivering consistency.
Basic marmalade principles are the same as those for other jams:
• Extract the maximum pectin. This is usually done by gathering the pips from the fruit, sometimes also the pulp and pith, in a muslin bag and boiling it with the juice before removing it and squeezing the bag to extract the soluble pectin.
• Ensure there is plenty of acid. This helps to extract the maximum pectin and gives a better set. Extra lemon juice is often used for this, but it’s not a particular problem for marmalade.
• Dissolve sugar completely before bringing the fruit and sugar mixture to a boil. This helps to prevent crystallisation
The aim is to extract pectin, and then to make a 60-65% sugar solution with the fruit by boiling off the water until this setting point is reached. I based this recipe on one for Sweet Orange Marmalade from Waitrose Food Illustrated magazine, adding a step to increase the pectin, as suggested in other recipes.
2 small pink grapefruit
9 blood oranges
500g granulated sugar
Zest the lemons, one grapefruit and 3 of the oranges using a vegetable peeler to remove just the zest. Finely julienne the zest.
Juice all the fruit. There should be just over 1 litre.
Add the pips, pith and remaining flesh from the fruit into a square of muslin. Add this to a pan of water and boil for 45 minutes. Leave to soak overnight.
The next morning, squeeze all the pectin from the muslin and add with the water to the juice, zest and sugar in a large pan. Heat gently to dissolve the sugar, then bring to a simmer and boil for 1.5 hours, or until temperature reaches 104 degrees C. Start testing the set on a cold saucer, looking for a wrinkle on the surface when it is pushed.
Let cool for 15 minutes or so before putting into sterilised jars (this helps make sure all the zest doesn’t float to the top).
This looks beautiful, and is quite tart because of the grapefruit. It’s possible that it would have benefited from the zest being blanched before adding to the marmalade to remove some of the bitterness.