Originally made from quinces the Greeks called this melimelon (honey fruit) and this was transformed into Portuguese as marmelo. In turn this became marmalada when referring to quince paste.
Although most citrus fruits can be made into marmalade it is the orange and less usually lemon or lime varieties that are most popular. Seville oranges are regarded as the best for marmalade as they have a high pectin content and this provides a good set.
Mrs Beeton, in her book Jam-making and Preserves offers twenty different marmalades but her basic orange marmalade recipe is as follows:
Take 12 Seville oranges, 2 lemons and some preserving sugar.
Slice the fruit thinly, removing inner pith and pips. Weigh it, and to each lb. add 3 pints of cold water. Let the whole remain covered in an earthenware vessel for 3 days, then turn the preparation into a preserving pan and boil gently until quite tender. Let it cool, weigh again, and to each lb. of fruit add 1 lb. of sugar. Bring to the boiling-point, skim well, and cook gently until the syrup stiffens quickly when tested on a cold plate. Turn into pots, cover with paper brushed over on both sides with white of egg, and store in a cool, dry place.
The recipe we used this year is provided by Pam Corbin in her book Preserves. www.amazon.co.uk/Preserves-River-Cottage-Handbook-No-2/dp/0747595321/ref=sr_1_1?s=books&ie=UTF8&qid=1518605724&sr=1-1&keywords=preserves
She uses 1kg of Seville oranges, 75ml lemon juice, 2kg demarara sugar.
Scrub the oranges, remove the buttons at the top of the fruit, then cut in half. Squeeze out the juice and keep to one side. Using a sharp knife, slice the peel, pith and all, into thin, medium or chunky shreds, according to your preference. Put the sliced peel into a bowl with the orange juice and cover with 2.5 litres of water. Leave to soak overnight or for up to 24 hours.
Transfer the whole mixture to a preserving pan, bring to the boil then simmer slowly, covered, until the peel is tender. This should take approximately 2 hours, by which time the contents of the pan will have reduced by about one-third.
Stir in the lemon juice and sugar. Bring the marmalade to the boil, stirring until the sugar has dissolved. Boil rapidly until setting point is reached, about 20-25 minutes. Remove from the heat. Leave to cool for 8-10 minutes - a little longer if the peel is in very chunky pieces - then stir gently to disperse any scum, pour into warm, sterilised jars and seal immediately. Use within 2 years.