how to seal a jar without a canner
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Canning is a process of food preservation that uses heat to kill mold, bacteria and enzymes that would otherwise spoil the food. The method is useful for a wide variety of fruit, but should not be used for vegetables, meat or fish because of the risks of food poisoning if it is not completed successfully. Canning can be undertaken by a number of different methods, but not everyone has a canner in their home. Follow the instructions below to learn how to seal a jar without a canner.

Oven Method

Preheat the oven to 300 degrees F.

Wash the Mason jars thoroughly, and rinse with clean hot water.

Wash the fruit. Split stone fruit in half and remove any stones or pits. Put the fruit into the jar and use the handle of a wooden spoon to push it down until the jar is full, and the fruit is firmly wedged in place.

Place the sugar and 1/2 pint water into the small saucepan. Bring to a boil and stir to dissolve the sugar. Add another 1/2 pint water. Bring to a boil again.

Pour the boiling syrup onto the fruit until it is within 1 inch of the top of the jar. Carefully knock the jar on the counter-top to remove any trapped air and top-up with syrup if necessary.

Put the rubber seals and caps on the jars but not the screw-bands.

Place the jars on a baking sheet lined with newspaper in the center of the oven and heat for 50 to 60 minutes.

Remove from the oven and place on a wooden surface to avoid cracking. Tightly screw on the metal bands while still hot and allow to cool.

Water bath method

Prepare the fruit and jars following steps 1 through 5 of the oven method.

Place the rubber seals and lids on the jars, and loosely screw the metal bands in place.

Put the jars in a large saucepan and cover with warm water. Slowly bring to the boil over 25 to 30 minutes. For soft fruit such as blackberries and raspberries simmer for two minutes. For stone fruit such as apricots or peaches, simmer for 20 minutes.

Remove the jars from the water, re-tighten the screw-bands and allow to cool on a wooden surface.

Pressure cooker method

Prepare the fruit and jars following steps 1 through 5 of the oven method.

Place the rubber seals and lids on the jars and loosely screw the metal bands in place.

Put the pressure cooker trivet in the pan and add 1 1/2 pints water. Bring to a boil.

Put the jars into the pressure cooker, close the lid and heat until steam comes from the vent. Place a 5-pound pressure control in place and maintain the pressure. For soft fruit such as blackberries and raspberries cook for one minute. For stone fruit such as apricots or peaches, cook for three to four minutes.

Remove from heat, and let stand for 10 minutes. Then remove the jars from the pan, and tighten the screw-bands and allow to cool.

Tip

Test for a good seal by removing the screw-band and trying to lift the jar by the lid. If the jar can be lifted, a vacuum has been formed and the jar sealed.