Canning: A beginner's guide

Step 1:

1. Start with jars designed for canning and always begin by sterilizing them.

2. Fill your canning kettle with water, add clean jars (tilting them to fill with water), and place upright on rack.

3. Bring water to a boil for 10 min. Leave them to sit in the canning kettle while you make whatever you are going to fill them with — reheating the water if necessary before you fill them. Hot preserves must always be put into hot sterilized bottles.

Step 2:

1. Use new 2 piece metal lids designed for canning.

2. Place the flat part of the lids you plan to use in a small pot and cover well with water. Bring to a simmer and simmer for 5 min to soften sealing compound.

3. Turn heat to low and keep lids in warm water until ready to seal jars. Unused lids may be dried off and stored for another time. Used lids (not rings) must be discarded.

Step 3:

1. Fill jars leaving the right amount of ‘headroom’ (the space between the top of your preserves and the rim of the jar) specified in the recipe — if it doesn’t say then leave ¼ inch.

Note: If you fill jars too full, preserves may seep out and interfere with a good seal. Leaving too much headroom may leave more air in the jar than can be forced out during the processing time and may also result in spoilage.

Read more: Blue Grape Jam recipe>

Step 4:

1. Wipe the rim of the jar clean before topping with heated canning lid.

2. Add metal ring and twist it until it is only fingertip tight. If the ring is too tight it may interfere with air escaping and result in a poor seal.

Step 5:

1. Bring the water in your canning kettle to a boil. Place filled jars upright on rack, making sure they are covered with at least 1-inch of water.

2. Cover kettle with lid and return water to a boil. Start timer for processing when the water in the kettle has come to a boil.

Note: Always boil kettle with the lid on so that preserves reach the highest possible internal temperature.

Step 6:

1. Carefully remove preserves from canning kettle and set on a cutting board or dishtowel to cool.

2. After several min you may hear slight ‘pings’ as lids pop down to seal. Check to make sure that lids are concave and do not move when you press down in the centre. Any jars that have not properly sealed can be kept in the refrigerator and used within 2 weeks.

3. When cool, carefully remove metal rings, and wipe jars to remove any liquid that has escaped during processing. Label sealed jars and store in a cool dark place until ready to use — ideally within the year.

Note: Never eat preserves that appear to have bulging lids, broken seals, mould or a bad odour.