Ruby grapefruit marmalade

Peel the grapefruit and remove most of the pith. Cut or chop the skin into rough pieces. Chop the segments and fasten in a piece of muslin cloth along with the pips and pith.
Place the muslin bag in a large saucepan along with the skin, juice and 300 ml water. Cover, bring to the boil, reduce the heat and simmer for about 30 minutes or until the skin is very tender and translucent.
Remove the muslin bag and press out the juice into the saucepan. Add the sugar and heat slowly until dissolved, stirring occasionally. Bring to the boil and boil until the marmalade is ready (to test, see Soft citrus marmalade). Pour into sterilised jars and seal.
Makes 2 jars marmalade.