Equipment
Large pot (15- 19 Liters or16–20 quart)
Water bath canner
Knife
Cutting board
Mandolin (Optional)
Large spoon or ladle
Canning funnel
Jar lifter
Lid lifter
Half-pint canning jars with lids and rings
Fine sieve or cheesecloth
Dishwasher or boiling water for jar sterilization
Ingredients
Whole kumquats – 900 g / 2 lb / approx. 25 fruit
Orange juice – 1.5 L / 6 cups
Bottled lemon juice – 125 ml / ½ cup
Powdered pectin – 57 g / 1 package / 7 tbsp
Granulated sugar – 1 kg / 5 cups
Preparation
Prepare Jars and Lids
Wash jars and keep hot using a dishwasher sanitize cycle or by boiling for 10 minutes.
Keep jars warm until filling.
Place lids in hot (not boiling) water for at least 10 minutes.
2. Prepare the Fruit
Wash kumquats thoroughly.
Slice into very thin rings, removing and discarding all seeds.
3. Cook the Fruit (First Cook)
Combine sliced kumquats, orange juice, and lemon juice in a large pot.
Bring to a boil, then reduce heat and simmer gently for 1 hour, stirring occasionally.
Remove from heat.
Cover and let rest for 12 hours (overnight).
4. Measure Sugar and Pectin
Combine powdered pectin with 50 g / ¼ cup of the sugar.
Set remaining sugar aside.
5. Cook Marmalade (Second Cook)
Return fruit mixture to the stove.
Add the pectin–sugar mixture.
Bring to a full rolling boil over medium-high heat, stirring frequently.
Boil for 10 minutes.
6. Add Sugar
Add remaining sugar all at once.
Return to a full rolling boil and boil hard for 4 minutes, stirring constantly.
Remove from heat.
7. Skim Foam (Optional)
Skim off any foam from the surface.
8. Test for Gel Set
Spoon a small amount onto a cold metal spoon and allow it to cool.
If thickened, it is ready.
If not, return to heat with a small amount of additional pectin and reboil for 1 minute.
9. Fill Jars
Ladle hot marmalade into prepared jars, leaving 6 mm / ¼ inch headspace.
Wipe rims, apply lids, and screw rings on finger-tight.
10. Process
Process jars in a boiling water bath, fully submerged:
0–1,000 ft: 10 minutes
1,001–6,000 ft: 15 minutes
Above 6,000 ft: 20 minutes
11. Cool and Store
Remove jars and cool undisturbed for 12–24 hours.
Check seals before storing.