Place crushed pineapple in a kettle. Add water, lemon juice, and sugar and stir well. Place on high heat and, stirring constantly, bring quickly to a full boil with bubbles over the entire surface. Boil hard for 1 minute, stirring constantly.
Remove from heat; add pectin, flavor extract, and coloring. Skim. Pour immediately into hot, sterile canning jars to 1/4-inch from top. Seal and process 5 minutes in boiling water bath.
This recipe yields 9 or 10 half-pint jars.
Variation: Use 10 drops oil of spearmint instead of extract.
Yield: 9 or 10 half-pints