A fresh pumpkin should be cooked before being frozen. The best candidate is solid and heavy for its size with no bruises or soft areas. The stem should not be shriveled.
To prepare a pumpkin for freezing, it is first washed in warm water. A gentle soap and brush should be used only if needed to clear away dirt. Next, the pumpkin is sliced in half using a serrated knife. The seeds and stringy pulp are removed with a spoon, paring knife, plastic scraper or ice cream scoop. Then the pumpkin is cooked in a microwave, standard oven or on the grill. At this point, the flesh is separated from the rind, which is discarded. The flesh is pureed in a food processor or blender before being put in freezer bags with excess air removed. Prepared pumpkin lasts nine to 14 months in the freezer.