Grapefruit Marmalade

the sharper, cleaner cousin of the Seville: peel shredded and softened, pith and pips boiled in muslin for their pectin, then the whole cooked hard to a translucent set

Origin: United Kingdom

From the journey of Grapefruit.

British marmalade is a technology before it is a recipe, and the technology is pectin. Citrus carries very little pectin in its flesh and a great deal in its pith, its pips, and the white membranes between segments, all of which are the parts a cook would otherwise throw away. Boiling those discards in a muslin bag alongside the fruit extracts the pectin into the syrup, and it is that, with sugar and acid, that produces a set. No commercial pectin is needed and none should be used. Grapefruit marmalade belongs to the same Scottish and northern English tradition as the Seville orange kind, and it arrived with the fruit itself at the end of the nineteenth century. It is markedly different in the jar: sharper, cleaner, and less sweet, with a bitterness that is broader and slower than the Seville's bright astringency. Where Seville marmalade tastes of a specific fruit, grapefruit marmalade tastes chiefly of bitterness and sugar in balance, which is a virtue on plain toast and a fault beside anything else. The one caution is colour. Pink and ruby grapefruit make a marmalade that begins a pretty rose and ends a dull amber, because lycopene degrades under prolonged heat. Cooks who want the colour must accept a softer set from a shorter boil, or use white fruit and stop worrying about it.

Ingredients

Marmalade

  • 1.2 kg grapefruit, unwaxed, about 3 large fruit
  • 2 whole lemons, unwaxed
  • 2.5 litre water
  • 2 kg granulated sugar

Equipment

  • 1 piece muslin square and kitchen string

Method

  1. Scrub the fruit. Pare the coloured zest from the grapefruit with a peeler and shred it as finely or coarsely as you like the marmalade. Halve and juice all the fruit, reserving the juice.
  2. Scrape the remaining white pith from the skins and put it, with all the pips, membranes, and squeezed-out lemon halves, into a muslin square. Tie it into a loose bag.
  3. Put the shredded peel, the juice, the muslin bag, and the water into a large preserving pan and leave overnight.
  4. Bring to the boil and simmer, uncovered, for about two hours, until the peel is completely soft and the liquid has reduced by roughly a third.
  5. Lift out the bag, let it cool enough to handle, and squeeze it hard over the pan until no more thick liquid comes out. Put a saucer in the freezer.
  6. Add the sugar and stir over a low heat until every grain has dissolved, then raise the heat and boil hard, without stirring, for 15 to 25 minutes.
  7. Test for a set: drop a teaspoon onto the frozen saucer, wait a minute, and push it with a finger. If it wrinkles, it is ready. If not, boil for three minutes more and test again.
  8. Rest for 15 minutes off the heat, stir once to distribute the peel, then pot into hot sterilised jars and seal at once.

Notes

Use unwaxed fruit, since the wax on supermarket citrus does not come off in boiling and gives a dull, faintly greasy set. White grapefruit gives the sharpest and most characteristic marmalade; pink fruit tastes milder and loses its colour to amber during the long boil, so accept that or use white. The lemons are there for acid and additional pectin and should not be left out. Makes roughly six 340 g jars, which keep unopened for a year in a dark cupboard and a month refrigerated once opened. A tablespoon of whisky stirred in at the end before potting is a Scottish variation and a good one.

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