How to sterilise jars for jams and preserves
Updated: Jan 18
Sterlising your glass jars before use is an important step. Whether you are a home producer cooking up some strawberry jam like this recipe on BBC Good Food. Or a large business producing a batch of chutney to sell at a market. It needs to be done.
Sterilising jam jars is required to remove all bacteria, yeasts, fungi and organisms from the jar so that when you use it for preserving, the food will remain fresh within the vacuum.
Sen5es top tip!
Make sure that your glass jars are stored at room temperature before putting them in the oven. Putting cold jars in to a hot oven can cause thermal shock which will cause them to shatter.
How to sterilise lids and rubber seals
If your are using jars with rubber seals like our kilnclip jars. These need to be removed and sterilised sperately. The same goes for any twist off or screw top lids that you have with the jars/bottles.
Wash them in warm soapy water and rinse.
Place them in freshly boiled water for a few minutes.
Leave to air dry on a clean sanitised surface.
How to sterilise glass jars
The oven method
Preheat your oven to 160°C/gas mark 3.
Wash your jars in hot and soapy water.
Rinse them thoroughly and place upside down on a baking tray covered with baking paper.
Leave in the oven for 10 minutes and remove from the oven
It's best to use the jars straight away. So ensure your product is also warm and it to the freshly sterilised canning jars.
The dishwasher method
This is by far one of the easiest methods as you can just load your dishwasher up with your canning jars and set it to run.
Fill your dishwasher with clean jars. If you are recycling jars make sure they have been rinsed out.
Set your dishwasher to the highest setting you can and set the cycle going. If you have a steam setting you can also use this.
Leave them to cool slightly and remove when you need to use them. As with the oven method it's best to use them straight away.
Boiling in a pan
If you're only doing a small quantity of jam jars this is an easy way of sterilising them.
Line the base of a large pot (big enough for all your jars/bottles) with a tea towel and stand your jars upright on it.
Fill the pan with water to cover the jars completely.
Bring the water to the boil and let it boil for 10 minutes.
Carefully remove the jars and put them upside down on a clean sanitised surface to drain.
Again you should fill them while they are still warm and freshly sterilised.
How do you sterilise your jars before use? Do you use a different method. Let us know below in the comments.
All the best
The team at Sen5es
All of the graphics for this blog were created by Saga Arndt.