The recipe I followed called this, "Marmalade." I would call it jam. Rather than peeling and chopping the rind, the oranges and lemons are sliced whole, and go through several steps to soften them. We all really enjoyed the taste and texture, but the appearance is less attractive than a clear marmalade. Oh, it is pretty, but opaque-like jam.
I added two tablespoons of Campari at the end, which at least helped the colour. It certainly solved the issues I've had with American oranges being too sweet. After all the experiments over the years with orange blossom water, Angustora, and the like, a couple tablespoons of bitter orange booze accomplished what I'd been trying to capture. So good, that's sorted.
The other oddity in the recipe is adding the lemon juice at the end, before bottling. I've been preserving quite some time, but have never run across that instruction. It didn't seem to impact the pectin/gelling as it was being bottled, but perhaps there is some long-term reason for it. I should think with five oranges and two lemons it was acid enough already.
I used a jam thermometer this year, but even at 220 degrees F. I thought it needed a bit more time based on the spoon test. Perhaps it is best not to rely on a singular method of testing gelling. This did come up with just about the perfect texture, which is a nice departure from my typical marmalade soup. Or I cook it to death. Grapefruit seems more susceptible overcooking.
Overall? I loved the soft, big pieces of fruit and rind that weren't challenging to eat-the rinds practically dissolve on toast. The bitter/sweet ratio was perfect, and if someone presented this to me as jam I'd be delighted with it, but as marmalade I'm not convinced. I'm not however worried about any going to waste.
From, Sunset Home Canning:
5 medium sized oranges
2 small lemons
3 cups water
6 cups sugar
1/2 cup lemon juice
1-2 tablespoons Camapri (my addition)
Rinse unpeeled lemons and oranges (my note-scrub the hell out of 'em). Halve lengthwise, thinly slice crosswise, discarding seeds (I left a few that I fished out later as they help with gelling). Place slices in a large 8-10 quart pot, add water and press down fruit to make an even layer. Cover and let stand at room temperature 8-24 hours (I did 14).
Bring fruit to a boil, uncovered over high heat, stirring. Reduce heat to low and cook, stirring occasionally for 40 minutes. Remove from heat, cover and let stand 4 hours.
Stir in sugar, bring to a boil over high heat, and keep stirring until sugar is dissolved. Continue to boil uncovered until mixture thickens and reaches 220 degrees F. (but do a manual gel test, either a spoon or saucer). As it begins to boil down, turn down the heat as it will stick and sputter.
Remove from heat, stir in lemon juice and Campari if using.
Ladle marmalade into hot, sterilized jars, remove air bubbles and wipe rims clean. Process ten minutes in a boiling water canner (adjust times to your altitude), with a five minute cool down still in the canner after heat is off. Cool 12-24 hours before testing seals. Makes 5 pints or about 8 half pints.