The recipe comes from Ball’s Complete Book of Home Preserving
Quote from the book:
Due to their extended cooking times, traditional marmalades have a slightly caramelized flavor that spells perfection to marmalade aficionados. Before making one of these long-boil marmalades, review the gel state tests …
Gel State Tests: When not using something like pectin to make a spread you need to make sure your mix has reached “gel state”.
The easiest and best way to do this is with a candy thermometer.
Orange Chilli Marmalade:
2 1/4 pounds of oranges thinly sliced (I used mandarine which creates more peels, a bigger orange might have less peels, depends what you like)
6 cups of water
zest of one lemon
juice of one lemon
3 dried chilli pepers (they recommend habanero or New Mexico chili)
9 cups granulated sugar
- In a stock pot combine oranges, zest, water, juice.
- Bring to a boil over high heat stirring frequently
- Add peppers
- Reduce to a gentle boil, partially covered, for 40 minutes stirring occasionally until fruit is soft
- remove and discard peppers
- Bring mixture back to a full boil stirring constantly
- Gradually stir in sugar
- Wait until mixture reaches gel stage (about 15 minutes)
- Ladle into hot jars leaving 1/4″ headspace
- Process jars in boiling water for 10 minutes