Tower Alexa: Citrus Trio Marmalade
Serving is variable
1 red grapefruit
900ml or one and a half pints of water
1.3kg or 3lb of preserving sugar
Wash the fruit, then remove the peel from the grapefruit and cut into thin strips. Cut in half and squeeze the juice into the
pressure cooker. Place the pith on a large square of muslin.
Halve the oranges and lemons and squeeze the juice into the pressure cooker. Remove any pips. Cut the oranges and lemons in half again and scrape to remove most of the pith.
Place the pips and pith on the muslin and tie with a piece of string. Shred the peel.
Place the fruit peels and muslin bag in the pressure cooker and add half of the water.
Fit the lid and lock by aligning the handles. Turn the pressure limiting valve to II.
Bring to pressure and cook for 10 minutes.
Release the steam naturally, then remove the pressure limiting valve.
Press down the safety lock button to unlock the handles and open the lid. Carefully lift out the muslin bag. Take care as the bag is hot. Squeeze over the pan, between two plates, to extract as much pectin as possible. .
Add the sugar and remaining water to the pan and stir to dissolve the sugar. Bring to the boil in the open cooker, stirring occasionally, until a setting point is reached of 105°C or 221°F, or test on a cold plate.
Leave for 15 minutes, to cool, then pour into warmed sterilised jars, cover and seal. The marmalade should keep for up to 6 months. Refrigerate once opened.