When making homemade jams, spreads and drinks, the recipe will often tell you to sterilise your jar – but what exactly does that mean? We show you how – don’t worry, it’s very easy!

Why do I need to sterilise jars and bottles?

Every jar or bottle you are using to store food needs to be sterilised, even if they are new. Anything that has a tight lid preserves the food inside, protecting it from bacteria outside the jar, but if it has not been properly sterilised, you could be trapping harmful bacteria within. Bacteria will rapidly reduce the shelf-life of your food and could be dangerous to those eating, so it’s very important to sterilise your jars – but thankfully it’s not that hard at all.

One of the most important things to remember is to make sure the jar/bottle and the food you are putting in it are the same temperature to avoid any breakages. Hot food in hot jars and cold food in cold jars.

How do I sterilise jars and bottles?

Sterilising really just means a really good clean so you need to wash the inside of the jar then steam or heat it to ensure that the jars remain clean while drying. There are two ways to do this.

In the dishwasher

This is the easiest of the two methods so if you have a dishwasher, it’s the best option to go for.

Fill your dishwasher with your clean jars (if using old jars, you will need to rinse them out first.)

Set your dishwasher to the highest setting or steam setting if it has one and put them through a cycle.

Leave to cool slightly in the dishwasher and remove each one as you need it.

In the oven

Wash the jars thoroughly using warm water and washing up liquid and rinse clean. Place a sheet of baking paper on one of the shelves of your oven (not at the bottom of the oven) and place the jars on the shelf – making sure they’re not touching each other.

Heat your oven to 140°C/210°F/Gas Mark 1 and dry out the jars for around 15-20 mins.