Basic Steps in Pressure Canning

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Discard jars with nicks or sharp edges. Screw the ring band on by hand as tightly as you comfortably can. Leave at least an inch headspace to allow for expansion. Place filled jars on the rack, using a jar lifter. Start timing the process when the pressure reading on the dial gauge indicates  pressure is  reached. Have ready a regular canning kettle or pressure canner as needed, jars, lids, ring bands, and other helpful accessories. Thoroughly wash canning jars and bands and discard jars with nicks or sharp edges on the rim that might prevent a good seal. Discard rusted or bent ring bands, for they will not tighten onto the jars properly. Scald jars, lids and rings lids in boiling water; keep in very hot water until time to use. Fill clean, hot jars one at a time. If necessary, you can reheat a jar by immersing it in the canning kettle full of hot water.   Leave at least an inch headspace to allow for expansion. Insert a knifeblade along the edge, moving around the jar to remove any air pockets. Run a narrow spatula down between the food and the side of the jar to release any air bubbles. With a clean, damp cloth, carefully wipe the jar rim, for food on the rim may prevent sealing. Remove a lid from the hot water and place it on a jar. (If lids stick together, plunge them into cold water; then submerge them again in boiling water.) Screw the ring band on by hand as tightly as you comfortably can. Place the rack in the canning kettle and fill the kettle about half full with hot water. As each jar is filled, set it in the canning kettle filled with hot (not boiling) water. When processing jars of food, place jars on the rack so steam can flow around the jars without the jars touching. Fasten canner lid securely. Leave weight off vent port or open petcock. Heat at highest setting until steam flows from the petcock or vent port. Maintaining high heat setting, exhaust steam for 10 minutes, then place weight on vent port or close petcock. The canner will pressurize in the next 3 to 5 minutes. Start timing the process when the pressure reading on the dial gauge indicates that the recommended pressure has been reached, or when the weighted gauge begins to jiggle or rock. Regulate heat under the canner to maintain a steady pressure at or slightly above the correct gauge pressure. Quick and large pressure variations during processing may cause liquid losses from jars. Weighted gauges on Mirro canners should jiggle about 2 or 3 times per minute. On Presto canners, they should rock slowly throughout the process. When the timed process is completed, turn off the heat, remove the canner from heat if possible and let the canner depressurize. Do not force-cool the canner. Forced cooling may result in food spoilage or loss of liquid from jars. After the canner is depressurized, remove the weight from the vent port or open the petcock. Wait 2 minutes, unfasten the lid and remove it carefully. Lift the lid away from you so the steam does not burn your face. Remove jars immediately after opening the canner and place on a towel with ample space for air circulation. Avoid a drafty area. Do not touch the jar lids until completely cool. Test for a good seal by pressing the jar lid with your finger; if it stays down when pressed, the jar is sealed. Do not turn jar upside down to test for leaks because liquid could seep between the lid and jar top, breaking the seal. Label each jar and store in a cool, dry place. Unsealed Jars: What to Do If a lid fails to seal, you must reprocess within 24 hours. Remove the lid, and check the jar-sealing surface for tiny nicks. If necessary, change the jar. Always use a new, properly prepared lid, and reprocess using the same processing time. The quality of reprocessed food is poor. Instead of reprocessing, unsealed jars of food also can be frozen. Transfer food to a freezer-safe container and freeze. Single, unsealed jars can be refrigerated and used within several days. Find out more about jars.