Preserve food by canning, freezing, and dehydrating
This at-a-glance guide shows how to preserve foods by canning, freezing, and dehydrating (or drying) them. People have been preserving food for eons. Newer, safer food preservation techniques and equipment enable you to stock your pantry or freezer with delicious, healthy foods. Pick your preferred method—water-bath canning, pressure canning, freezing, or dehydrating—and follow these basic instructions.
Water-Bath Canning
- Gather supplies and equipment; keep jars hot.
- Prepare food.
- Fill jars, leaving proper headspace and releasing air bubbles. Put on lids and hand-tighten screw bands.
- Place jars in water-bath canner.
- Bring water to boil and allow to boil for amount of time specified in recipe.
- At end of processing time, remove jars and allow to cool completely.
- Test seals.
- Store!
Pressure Canning
- Gather supplies and equipment; keep jars hot.
- Prepare food.
- Fill jars, leaving proper headspace and releasing air bubbles. Put on lids and hand-tighten screw bands.
- Place jars in pressure canner.
- Close and lock canner.
- Process jars as outlined in recipe.
- At end of processing time, allow pressure to return to 0.
- Remove jars from canner and allow to cool completely.
- Test seals.
- Store!
Freezing
- Gather supplies.
- Prepare food.
- Place food in freezer containers, leaving specified headspace (if using rigid containers) or pressing out all excess air (if using freezer storage bags).
- Slightly chill food or, if it was blanched, allow to come to room temperature.
- Loosely pack food in freezer.
- When completely frozen, repack more tightly in freezer.
Dehydrating
- Gather supplies.
- Prepare food.
- Arrange food on dehydrator trays.
- Dry at specified temperature, occasionally turning food and rotating trays.
- Check for doneness, using guidelines in recipe for what properly dried food looks and feels like.
- Place in airtight storage container and store in cool, dry place out of direct sunlight.
Adjustments for high-altitude canning
Home cooks who live at high altitudes may be used to adjusting recipes; high-altitude adjustments apply to home canning, as well. Canning food safely requires your filled jars to be processed at a specified temperature or pressure level for a specified amount of time. If you live at altitudes higher than 1,000 or 2,000 feet above sea level, adjust your canning recipes for food safety.
- Water-bath canning: Generally, recipes are written for water-bath canning at altitudes less than 1,000 feet above sea level. If you live higher than 1,000 feet above sea level, follow these guidelines:
For processing times of less than 20 minutes: Add 1 additional minute for each additional 1,000 feet of altitude.
For processing times of more than 20 minutes: Add 2 additional minutes for each 1,000 feet of altitude.
- Pressure canning: Pressure canning recipes are generally written for altitudes of less than 2,000 feet above sea level. If you live higher than 2,000 feet above sea level, make this adjustment: Increase pounds of pressure by 1/2 pound for each additional 1,000 feet.
If you don’t know your altitude level, you can get this information from many sources. Try contacting your public library, a local college, or the cooperative extension service in your county or state. Or go to What Is My Elevation? and simply type in your zip code.
Tips for successful and safe canning
Keep safety in mind whether you’re water-bath canning or pressure canning. By canning foods safely, you can prevent kitchen accidents and food spoilage. Increase your chances for successful canning and maximum safety by following these guidelines:
- Use recipes made for modern-day canning (from about the year 2000 or newer) and follow them exactly. Don’t increase or decrease your ingredients, processing time, or pressure level (for pressure canning).
- Don’t double recipes. If you want more than one recipe, prepare the recipe more than once.
- Use the proper ingredients. Select only unblemished and not overly ripe fruit or vegetables, and when a recipe calls for salt, use only canning or pickling salt.
- Use jars and two-piece lids approved for canning. Metal lids are only for single use; do not reuse them. You can use plastic reusable lids multiple times.
- Always label and date your finished product and use within one year of the date of processing.
- Periodically check your jars for any signs of spoilage and, if in doubt about the quality or safety of a preserved product, dispose of it without tasting.
Tools and equipment for canning and preserving
If you plan to can, freeze, or dry (dehydrate) your food, you’ll need some special tools. The equipment involved with canning or preserving food is designed for efficiency and safety, so be sure you to use the correct tools. If you have them already, great! If not, add them to your shopping list.
- Tongs: Have tongs ready for lifting hot foods out of boiling or simmering water. Any type will work, but tongs with a locking mechanism are a good idea, as this keeps them out of the way when not in use.
- Candy thermometer: Find a good-quality thermometer, with a clip for attaching it to the side of a pot. This item is so useful that it is a good idea to have a backup in case one breaks while you are using it.
- Jar lifter: This tool is a specialized set of tongs. Its rubberized ends fit securely around any size of canning jar, to lift them in and out of your canner.
- Canning funnel: Used for canning foods, this wide-mouth tool keeps the rims of jars clean. It can also be used to fill freezer bags neatly.
- Canning jars: Canning jars are made from tempered glass to withstand the high heat and pressure of your canner. Both narrow- and wide-mouth jars are available, with wide-mouth being the easiest to remove the food from once it is canned.
- Water-bath and/or pressure canner: If you’re going to can, you must use the appropriate canner. For canning high-acid foods (fruits, jellies, relishes, and pickles), get a water-bath canner. For low-acid foods (vegetables and meats), get a pressure canner.