Sterilize your jelly jars by washing them in hot, soapy water or by running them through the dishwasher. You can also place them in a pot of boiling water for about 10 minutes to sterilize. Keep the jars warm while you prepare the jelly.
2. Cook the Mountain Dew Jelly:
Pour the Mountain Dew and lemon juice into a large pot.
Sprinkle the fruit pectin over the soda mixture and stir to dissolve. Let it sit for about 5 minutes before heating, as this helps activate the pectin.
3. Bring to a boil:
Bring the Mountain Dew mixture to a boil over medium-high heat. Stir constantly to prevent the soda from overflowing.
Once it reaches a rolling boil, add the granulated sugar all at once, stirring continuously to dissolve it. If you choose to use butter (to reduce foaming), add it now. Continue stirring.
4. Boil the mixture:
Once the sugar is fully dissolved and the mixture is boiling again, let it boil for about 1-2 minutes while stirring. The jelly should start to thicken and become syrupy. To test if the jelly is set, drop a spoonful of the mixture onto a cold plate and let it sit for a minute. Run your finger through the jelly, and if it wrinkles and holds its shape, it’s ready. If not, continue boiling for another minute and test again.
5. Add citric acid (optional):
If you’d like to add a bit more tartness, sprinkle in the citric acid at this point, and stir to combine.
6. Ladle the jelly into jars:
Once the jelly has reached the desired consistency, carefully ladle it into the prepared, warm jars, leaving about 1/4 inch of headspace at the top.
Wipe the rims of the jars with a clean, damp cloth to remove any residue.
7. Seal and process:
Place the sterilized lids on the jars and screw on the bands until they are just fingertip tight (don’t overtighten).
Process the jars in a boiling water bath for 5-10 minutes to seal them properly. The water should cover the jars by about an inch. After processing, remove the jars from the water and let them cool completely.
8. Check the seals:
Once the jars have cooled, check the seals by pressing down in the center of each lid. If it doesn’t pop back, the jar is sealed. If any jars didn’t seal, store them in the refrigerator and use them within a few weeks.
9. Store:
Store your Mountain Dew Jelly in a cool, dark place. It will be good for about 6-12 months if properly sealed.
