These rules are listed in the approximate order of the canning procedure:
1. Before starting to work, examine all jars and lids for possible small chips, knicks and other defects by running your finger tips around the jar rim. Should the sealing rim of a jar or lid be chipped or otherwise damaged, discard it, since it will not permit an airtight seal.
2. Cleanliness is especially of utmost importance. Wash canning jars in hot soapy water, then rinse them in clean, hot water. If mold has formed in used jars (because they were stored in a damp cellar), submerge jars in boiling water for ten minutes. Mold and fungus spores are not killed at temperatures below 212°F, so the temperature of a dishwasher (about 140°F) is not high enough.
3. Carefully examine rubber rings before processing. Possible cracks can be best detected by holding the rubber ring between the thumbs and forefingers of both hands and tugging lightly while turning bit by bit. A safe seal can only be achieved by using perfect rubber rings. Always use new rubber rings.
4. Submerge rubber canning rings in boiling water for 2-3 minutes. Leave them in the hot water until they are needed. It is not necessary to sterilize jars and lids unless the processing time is less than 10 minutes. (Fruit juices are processed only 5 minutes, for example.) To sterilize jars and lids, boil them for 10 minutes.
5. When filling hot foods (example, precooked hot jam) into the jars, place the jars on a towel, rack or wooden cutting board to keep jars from cracking.
6. What is the proper headspace?
Pack foods up to within ½ inch of the jar rim; add liquids as well as sugar syrups to the same height. Some foods can be packed raw into jars with boiling liquid added. Other foods should be precooked and packaged hot with hot liquid into jars. See each recipe for packing instructions.
7. Sweetening (natural and artificial)
According to long experience, recently confirmed by new research, sugar should not be added dry to the foods, but as syrup. Add the required amount of water and bring the syrup to a rolling boil for a short time. Pour the hot syrup over the food in the jars. Artificial sweeteners should not be used for canning. They can be added at the table.
8. After filling the jars, carefully wipe the jar rim.
9. When using the WECK Round Rim jars, apply the rubber ring to the sealing rim of the lid. It is best to apply the rings before filling the jars. Leave the lids with the attached rings in hot water, until both can be placed together on the jar. The uncomplicated sealing method of the WECK jars prevents dislodgment of the rubber canning ring and seals which are not airtight can be avoided.
10. Closing the packed jars by means of spring clamps:
During processing, the jar is then tightly closed by means of two canning clamps made of rust-proof stainless steel and having an exactly adjusted, permanent spring action. Hold the canning clamps, arranged directly across from each other, into the stacking depression in the lid. Then press them down until they click under the protruding rim of the jar (illustrations page 5).
11. In the canner, the jars should be placed on a rack. It does not matter if the jars touch each other or the kettle wall. They should not, however, be wedged into the canner so tightly that the jars cannot move at all; a little space for jar movement is necessary for good results.
12. After you have placed the jars on the rack in the canner, fill water into the canner high enough so that the jars are completely submerged in the water. If you place two or more rows of jars on top of each other, or if low jars are processed together with high ones, the water level will always depend on the height of the highest jars. If two layers of jars are being processed, a second rack must be used between the layers so that the water can circulate freely around all the jars. The jars should be completely covered by one to two inches of water. The spring action of the clamps keeps them sealed, and no water from outside can enter the jars.
When you start to process the jars, the temperature of the water bath has to have approximately the same temperature as that of the jar contents. Jars filled with raw-packed food therefore must be started in warm water, jars filled with hot food ( in the case of precooked food) accordingly in hot water. In no case, however, should you add hot or boiling water to the canner for jars filled with raw-packed food; the water reaches the prescribed processing temperature too quickly, but the jar contents are not yet heated up to the required temperature. Thus, the thermostat merely indicates the temperature of the boiling water, but not the temperature of the food in the jars. The results: the processing times prescribed by the recipes are insufficient; failures will then be inevitable because not all the bacteria and spores have been eliminated inside the jar; the processing temperature of the interior was simply too low. When placing the jars in the canner, it is absolutely necessary that the food in the jars have roughly the same temperature as the water that is poured into the kettle. And remember: always heat the canner slowly.
14. When processing your jars, carefully observe the temperatures and heating times specified in the recipe section of the WECK Home Canning Guide. Do not cut down the processing times under any circumstances! The processing time starts when the canner reaches a full rolling boil. The time needed to heat up the water in the canner does not count! The thermostat then holds the set temperature by controlling the heating element which keeps the water at a constant temperature.
15. When the required processing time is up, remove the jars from the canner. Place jars on a rack, wooden cutting board, or towel, and allow them to cool down undisturbed. The jars should not cool down in the water bath, since in that case the heating time is lengthened and the canned foods may become too soft or turn unsightly due to overcooking. Nor is it advisable for the same reason to cover the processed jars with a towel. Keep jars away from a cold draft, and avoid placing them on a cold surface or cooling them quickly by means of cold water.
16. Very important:
After removing the processed jars from the canner leave the canning clamps on the jars until the jars are completely cooled. When the jars are cold however, it is absolutely necessary to take off the clamps. They are now no longer required to keep the jars sealed (refer to page 7-8). If you remove the canning clamps, you can easily check to see if the jar is actually sealed by trying slightly to lift off the lid (so-called lid-lifting test). In the first few days after processing you should carry out sealing checks of your jars by this lid-lifting test and always before you open each jar. Note: in the seal on the WECK jars, the pull tab of the rubber ring on the sealed jars quite clearly faces downwards. If you arrange the jars correctly on your shelves, you can simply check them by visual inspection to ensure that they still face down. This facet of the seals will prove the stackability of the WECK jars and arrange them on top of each other.
17. In the storage area, the jars should not be subjected to direct sunlight. The room has to be kept frost-free. It is not necessary that the canned jars be stored in a cool basement or cellar. It is sufficient if they are kept at room temperature.
18. In order to open your canning jars, pull the protruding tab of the rubber ring, until you hear a "ps-s-st", indicating that air has been sucked into the jar. The vacuum in the jar has thus been equalized, and the lid and rubber ring can now be easily taken off. Never use sharp objects, such as knives, scissors, or screwdrivers, since they will damage the jar rim or lid. If the rubber rings sticks to the jar or the tab is torn off, the jar can be opened easily by attaching three canning clamps and placing the jar upside down in hot water for several minutes.