Put safety first when you prepare and serve home-canned foods. Due to the risk of botulism, never consume low-acid foods that are not canned according to the recommendations in this publication or other USDA-endorsed source. Such foods should be discarded, even if you detect no signs of spoilage.
- Select high-quality poultry, meat, and game using only the cuts and preparation steps described in this publication.
- Always can meats and other low-acid foods in a pressure canner. Boiling water canners and steam canners do not produce temperatures high enough to kill botulism-causing bacteria and other spoilage organisms.
- Never can in an oven (electric, gas, wood-burning, or microwave).
- Be sure the dial gauge on your pressure canner is accurate. Have it tested once a year or more often if you do a great deal of canning or drop the lid.
- Each time you use a pressure canner, check to see that the petcock or vent port, and safety valve are not blocked.
- Follow directions exactly for filling jars. Over-packed jars do not heat as evenly as correctly packed jars.
- Always exhaust (remove) air from a pressure canner by venting for 10 minutes before letting pressure build. Cold air trapped in a canner will cause inadequate heating of the jars and under-processing of the food.
- Increase pressure at altitudes above 1,000 feet for weighted-gauge canners or 2,000 feet for dial-gauge canners to reach the proper temperature (240°F) for pressure canning.
- After processing, allow canner to cool naturally. The cool down time is factored into the processing time and organisms continue to be destroyed during this time. Force cooling a canner can result in an unsafe product.
- Never can meat products or combination foods for which you do not have research-based processing times. A safe canning time cannot accurately be determined at home.
Due to the risk of botulism, it is extremely important that meat, poultry, and game be canned according to the USDA-endorsed recommendations in this publication. Follow the procedures or recipes specified for each product precisely.
For an extra measure of safety, boil home-canned meats before eating them. At altitudes below 1,000 feet, boil for 10 minutes; add an additional minute of boiling time for each additional 1,000 feet of elevation.
Selection of Equipment
A pressure canner is a specifically designed kettle with a cover that can be clamped or locked down to make the kettle steam tight. It is designed to heat foods at temperatures higher than the boiling water canner. It must be equipped with an accurate pressure gauge to register the steam pressure in the canner.
There are two types of pressure canners: a dial gauge canner and a weighted gauge canner (Figure 1). One manufacturer makes a dual-gauge canner. Read the manufacturer’s instruction manual for information on when and how to use either the dial gauge or the weighted gauge.
A pressure canner must be large enough to hold at least four quart size jars standing upright to be safe for canning. Pressure saucepans are not suitable for canning.