- Place watermelon in a food processor.
Line a strainer with four layers of cheesecloth and place them over a bowl.
- Cover and process the watermelon until it is pureed.
Discard watermelon pulp from the cheesecloth.
- Place pureed watermelon in a prepared strainer and cover the edges of the cheesecloth.
- Let sit for 10 minutes.
Stir in lemon juice, sugar, vinegar, and food coloring as desired.
- Place the liquid in a large saucepan.
Remove the mixture from the heat.Skim off the foam.Ladle the hot mixture into five hot half-pint jars.
- Bring to a full rolling boil over high heat while constantly stirring.
- Stir in pectin.
- Continue to boil 1 minute while stirring constantly.
Note: Make sure to leave a minimum of 1/4-in. headspace.Place jars into canner with simmering water.
Note: Make sure that they are entirely covered with water.Bring to a boil for 10 minutes.Remove jars and let cool.
The process of making smoothies has existed for hundreds of years, but smoothies were only called smoothies after the invention of the blender.