Blanch vegetables before freezing them. Blanching is the process of heating or scalding vegetables in boiling water or steam for a short time. This slows or stops enzymatic action that reduces flavor, color and texture. It also removes dirt and organisms from vegetable surfaces; helps retard vitamin loss; and wilts or softens vegetables, making them easier to pack in freezer containers.
Use a wire blanching basket and covered saucepan or a wire basket into a large kettle with a fitted lid. Use 1 gallon of vigorously boiling water per pound of prepared vegetables. After putting vegetables into the basket, lower it into the container and begin blanching time as soon at the water returns to a boil, usually within one minute. If it takes longer to return to a boil, you’re using too much vegetable for the amount of water. Be sure to keep heat high for the total blanching time.
Quickly and thoroughly cool vegetables to stop the cooking process. Otherwise, they’ll be overcooked and lose flavor, color, vitamins and minerals. Inadequate draining before freezing, slow freezing or temperature fluctuations above 0 degrees Fahrenheit might cause this. It can affect frozen vegetables’ texture and appearance.
Frozen food is only as good as the quality of the fresh food. So choose high-quality products at optimum maturity and freshness. Although freezing doesn’t kill all bacteria, yeasts and molds in food, it does keep them from rapidly multiplying when the food remains at 0 degrees F or less. However, surviving organisms can multiply when the food is thawed.
When canning foods, wash and blanch them before filling jars. Do not over pack jars as this can cause inadequate processing and result in unsafe food. Nearly all fresh vegetables must be processed in a pressure canner for the required USDA processing time. Pickled foods, such as acidified tomatoes and pickles, can be safely processed without pressure in a boiling water bath.
It's very important to allow steam to escape for 10 minutes before closing the valve or putting the weight on the vent. This allows the inside temperature to correspond to that of the pressure gauge.
If you discover an unsealed jar within 24 hours, the food can safely be re-canned. Remove the lid and check the jar sealing surface for tiny nicks. Change the jar if needed and add a new, treated lid; then reprocess using the same original processing time.
Properly canned food will retain optimum eating quality for at least one year when stored in a cool, dry place. Canned food might lose some quality in a few weeks or months if stored in a warm place (near hot pipes, a furnace or in direct sunlight), depending on the temperature. Dampness might corrode cans or metal lids, causing leakage and food spoilage.
For more information on canning, freezing and other food preservation topics, contact the Logan County Cooperative Extension Service.