Canning is a method of preserving food that involves heating filled jars of food to a specified temperature for a specified time. This heating is known as "processing" and is essential for the food safety of all home canned foods. Processing destroys microorganisms that enter the jar upon filling and allows air to be vented from the jar to create an airtight vacuum seal as the product cools.
1. Before beginning, review the following information and assemble all equipment and ingredients.
2. Visually inspect canning jars for nicks, cracks, uneven rims or sharp edges that may prevent sealing or cause jars to break. Screw bands may be reused. Check to ensure screw bands show no rust, are in good condition and fit properly on jars. Discard any jars and screw bands that are not in good condition. Use new metal lids each time to ensure a vacuum seal. Wash jars, screw bands and lids in hot soapy water. Rinse well.
3. Sterilize jars just before use. To sterilize jars, place upright into rack in a boiling water canner. Cover with room temperature water. Cover canner with lid. Place over high heat and bring to a boil; boil rapidly for 15 minutes or as required (see Canning at High Altitudes).
Raise rack holding jars and hook handles on sides of canner. Leave water-filled jars in canner until ready to fill with fruit. Prepare metal lids according to manufacturer’s instructions; leave in hot water until ready to use. Screw bands do not need to be sterilized.
5. Drain one jar at a time into sink and fill immediately with prepared fruit using either a Hot Pack or Raw Pack. The Hot Pack allows more fruit to be packed into jars and helps to maintain the colour and texture of fruit.
Hot Pack: Simmer fruit in syrup (see Canning Liquids)
in a saucepan for 5 minutes. Fill jars with hot fruit; cover with boiling syrup, leaving 1/2 inch (1.25 cm) headspace. Headspace is the space at the top of the jar between the underside of the lid and the top of the food or liquid.
Raw Pack: Pour boiling syrup over raw fruit in jars, leaving 1/2 inch (1.25 cm) headspace.
6. Remove air bubbles by sliding a non-metallic utensil, such as a narrow rubber spatula or plastic knife, between jar and fruit. After removing air bubbles, add additional syrup, if required, to maintain 1/2 inch (1.25 cm) headspace. Wipe jar rim thoroughly with a clean damp cloth.
7. Center lid on jar. Apply screw band just until “fingertip tight”. Do not over tighten. “Fingertip tight” allows some give between the lid and jar and allows air to escape during processing. This creates a vacuum seal as the product cools.
8. Place filled jar into the raised canner rack. Repeat process with remaining jars. When all jars are filled or canner is full, lower rack into hot water. Be sure jars are covered by at least 1 inch (2.5 cm) of water; add boiling water, if required. Place lid on canner and turn heat to high.
9. When water returns to a full rolling boil, begin counting processing time (see Canning Specific Fruits
). Reduce heat to maintain a gentle and steady boil for the required time. Turn off heat and remove canner lid. Allow boil to subside, then lift jars without tilting and place them upright on a rack, dry towel or a cutting board to cool in a draft-free place. Do not retighten screw bands or turn jars upside down as seals may be broken. Allow jars to cool undisturbed for 24 hours.
10. After cooling, check jars for vacuum seal by pressing on center of each lid. Sealed lids curve downward and do not move. Refrigerate any unsealed jars and use fruit within one week, or freeze or reprocess within 24 hours. Reprocessing fruit is not recommended as it gives a significantly overcooked product. However, if reprocessing is desired, empty jars, reserving fruit and syrup. Repeat all steps. If a sealed jar becomes unsealed after some time in storage, this indicates spoilage from microbial growth. Discard the contents of the jar.
11. To store sealed jars, wipe with a clean damp cloth. Remove, wash and dry screw bands. Store separately or replace loosely on jars, as desired. Label jars and store in a cool dark place. As a guideline, use home canned foods within one year.