You will need two pans - one with a tight-fitting lid to cook the fruit, and a larger, open pan for the second stage when the sugar is added and it has to be brought to a full rising boil, writes Wendy Brandon.
This amount will fill about 8 x 340g jars, which should be washed, dried and ready before you start.
The total weight of the fruit should be about 2.5lbs/1.1kg.
* 2 grapefruit
* 3 oranges
* 1 lemon
[I use whatever combination of citrus fruits I might have, including limes]
Scrub the fruit clean, cut the lemon and oranges in half and the grapefruit into quarters and put them in a pan with a tight-fitting lid. Add 4 pints/2.2 litres of water. Bring to the boil and then turn down the heat and simmer on a low heat for about an hour - until the fruit skins are soft when you push a knife into them.
Take the fruit out of the water and put it on a plate to cool. When it is cool enough to handle, cut it neatly into slices, depending on how coarse cut you like your marmalade. (There is no need to separate the pulp from the skin - just take out the seeds. This is the only part of the fruit that is thrown away. Do not throw away the water the fruit was cooked in.)
Tip the cut-up fruit back into the water it cooked in and bring back to the boil in a larger pan - preferably a preserving pan with sloping sides. Stir in (until it dissolves) 3.25lbs/1.5kg white cane sugar. Keep it on the highest heat possible and it will come to a rising boil. After about 15 minutes, it will stop rising and start to fall slightly as it boils off some of the water. Give it the occasional stir to make sure it is not sticking to the bottom of the pan. Soon it will start to spit with a plopping sound.
Take it off the heat, stir it well, place about half a teaspoonful on a cold saucer and put this in the fridge for a few minutes. When you take it out, push it gently along the saucer. If the surface forms a skin and it wrinkles, it is at setting point. [Note I found this took around an hour]
Pour it into the bottles while hot (easiest to do with a small jug), wipe any spills off the neck of the jar and screw down the caps tightly.
If the jam on the saucer did not wrinkle, put it back to cook for another five minutes - on a high heat - and then test it again. If you have a candy thermometer, put this in the pan, hooking it over one of the handles before you start to boil it. When this reaches a temperature of 220F/104C, the jam is at setting point. Never put a cold thermometer into a hot pan - warm it up along with the marmalade.
I'm a Minister with Amida Shu, a Pureland Buddhist Order. Now semi-retired, I teach on-line and hold Pureland Buddhist sangha gatherings in Perth, Scotland. This site is mainly Buddhist in content. I share the teachings of the Head of our Order, Dharmavidya David Brazier