Pumpkin and Winter Squash
Posted: October 15, 2012
Smaller pumpkins and squash work well to use fresh. Larger ones are suitable for freezing and, with special procedures, for canning. Choose ones with a hard rind and stringless, mature pulp. There are less safety issues when freezing pumpkin and winter squash than with canning it.
The growing conditions for pumpkin and squash are a good source of surface bacteria and other spoilage organisms. It is necessary to wash them thoroughly before taking a knife through the skin which could force surface bacteria down into the flesh. Scrub them with a vegetable brush under cool running water before cutting and cooking. Do not use soap or detergent.
Pumpkins and winter squash that have been properly harvested and stored will keep for several months. Most varieties will keep up to 3 months if stored between 45 to 50°F and at moderate humidity. Spaghetti squash will keep about 2 months. Hubbard squash will keep well up to 6 months.
Freezing Pumpkin and Winter Squash
To freeze pumpkin and squash as a puree or sauce, cook it until soft in boiling water. It may also be steamed, cooked in a pressure cooker, or baked in an oven. Remove the pulp from the rind and mash. For a smoother sauce, put it through a food mill, blender, or food processor. Spaghetti squash does not need to be mashed. To cool, place pan containing pumpkin in cold water and stir occasionally. Use two pans to chill pumpkin if you have a large amount. Then freeze in rigid plastic containers or freezer jars leaving headspace for expansion. Package in amounts that you will use for a recipe such as two cups for a pumpkin pie.
It can also be packed in zip-type freezer bags that have had excess air removed and placed on a tray so that they freeze flat. This will make them easier to stack when frozen. Because the bags are thinner, the product will thaw more quickly than that frozen in square boxes. An easy way to remove thawed pumpkin from a freezer bag is to clip a corner and push the puree out like you would from a frosting bag.
Some stir-fry and skillet recipes and casseroles call for cubes of butternut squash. These directions for freezing cubes of squash are from Nebraska Cooperative Extension. Blanch washed and peeled cubes of raw squash for 3 minutes—just until heated through, drain, and chill in cold water. Keep blanched cubes in a colander while chilling to avoid their breaking apart. Drain thoroughly and spread in a single layer on trays. When completely frozen, put in freezer bags or containers. The frozen cubes can be added directly to your recipe.
Pumpkin products such as pumpkin bread or pumpkin soup freeze well. However, baked pumpkin pie made with a custard base will become watery when frozen. Freeze pumpkin pie filling without the eggs and milk and use it thawed like a commercially canned pumpkin pie mix. Also, freeze pumpkin butter and other pumpkin spreads.
Canning Pumpkin and Winter Squash
Because pumpkin and winter squash are low acid foods, it is not safe to can them in a boiling water bath. There are no research tested recipes for safely canning pumpkin jams, jellies, conserves, or pumpkin butter. These products must be stored in the refrigerator or freezer and treated the same as fresh pumpkin.
The only safe method to can pumpkin or winter squash is to cut the peeled product into 1 inch cubes and add them to boiling water; cook them for 2 minutes and then pack the hot cubes into hot jars; fill the jars with boiling hot cooking liquid. Allow 1 inch headspace. Process at 11 pounds pressure in a dial gauge pressure canner or 10 pounds pressure in a weighted gauge pressure canner. Process pints for 55 minutes and quarts for 90 minutes. Do not can mashed or pureed pumpkin because the puree is too dense for adequate heat to penetrate to the center of the jar during processing. Spaghetti squash is not suitable for canning.