Canner Safety  and Annual Maintenance

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Annual Safety Testing Many canners are passed down or bought at estate sales or yard sales. Often there's no way to know if they are working properly without being tested. Even newer canners should be tested to ensure the safety of the food being processed Dial gauges should be tested annually or more often if used frequently. Your local Cooperative Extension will perform this test for you. If the gauge is out of calibration, it will need to be replaced or sent back to the manufacturer for re-calibration. If you cannot get it tested nearby, write to see if the manufacturer can do it. The manufacturer's name and address will be pressed into the canner or on a plate attached to it. Ask for shipping instructions. Pack it like fine crystal and label the package "fragile." If you do not have an instruction book for your canner, write for one. If the gauge reading is off one pound or more, buy a new pressure gauge. If it is off less than one pound, tie a tag on the canner to remind yourself of the difference and adjust to pressure reading to allow for difference. The weighted pressure control on canners does not need to be checked. Keep it clean and rust free. Some canners have a gasket. These gaskets are made of rubber or rubber-like compounds to keep steam from leaking out around the cover. You can remove and replace most gaskets as needed. Some only need to be turned to ensure a tight seal. Replace a worn, stretched or hardened gasket with a new one. Refer to the canner instructions for directions. Leakage makes it difficult to reach the right pressure and may cause the canner to boil dry.  Pressure Canner Maintenance Keep the manufacturer's instruction book that comes with your pressure canner. Reread the directions at the beginning for each canning season and follow them carefully. If you have lost the manufacturer's book, write for a new one. Give the model number and any other information you find on the canner. Before the canning season, put water in the canner and bring it up to pressure in the usual way to see that it is in good working order. Allow time for repairs, if needed. Have a dial gauge checked before the canning season, and also during the season if you use the canner often. Ask your county Extension home economist, dealer or manufacturer about checking it. Cleaning and Storing Pressure Canners Wash thoroughly after each use, but don't put the cover in water because this will damage a dial gauge and may cause vents to become clogged. Never run water over the dial gauge. Wipe the cover with a soapy cloth and then with clean damp one. Clean the vent pipe by drawing a pipe cleaner or string through. Wash gasket and replace in cover. After use, clean your canner, being careful not to immerse the dial gauge on your pressure canner, if it has one. Dry the canner and store it with crumpled newspapers or paper towels in the bottom and around the rack. This will help absorb moisture and odors. Place the lid upside down on the canner. Never put the lid on the canner and seal it. For long term storage sprinkle a little baking soda over the bottom to keep down odors and control moisture. The darkened surface on the inside of an aluminum canner can be cleaned by filling it above the darkened line with a mixture of 1 tablespoon cream of tartar to each quart of water. Place the canner on the stove, heat water to a boil, and boil covered until the dark deposits disappear. Sometimes stubborn deposits may require the addition of more cream of tartar. Empty the canner and wash it with hot soapy water, rinse and dry. Store a canner carefully. Make sure it is clean and dry before you put it away at the end of the season. Crumple newspapers inside the canner to absorb moisture and odors. Some manufacturers recommend turning the cover upside down on the canner. This is designed to prevent odors in the canner and to protect the valves and gauge.