If you’re interested in making jams, chutneys and pickles, you will need to sterilise your glass jars to avoid spoilage. This comprehensive guide on how to sterilise glass jars, bottles and associated lids should tell you all you need to know.
I love preserving food. When produce is in season and cheap or you get a glut of something in the garden or allotment, there’s nothing more satisfying than jarring that produce up to keep you going through the coming year. I also love giving jars and bottles of deliciousness away to friends, family and neighbours. They can make excellent gifts.
Why do You Need to Sterilise Glass Containers?
Glass is a wonderful material and it has many benefits. If you want to preserve food for as long as possible, however, it’s really important that you sterilise your glass jars or bottles just before you fill them. This applies to new glass containers and lids as well as previously used ones. You should also sterilise metal lids as well as the rubber rings that accompany kilner type jars.
Why? Because if bacteria aren’t properly removed, your precious preserves may spoil. They could even be dangerous. Botulism is a very nasty form of food poisoning which can be caused through poor preserving methods.
How to Sterilise Glass Jars and Bottles
Once you’ve made your first batch of jam, chutney, cordial or whatever, you’ll sail through this process. It will become a standard part of your preserve making process. It’s really quite easy, you just need to get organised. You want your glass containers to be sterilised, dry and warm when your preserves are ready to be canned.
How to Sterilise Glass Jars in the Dishwasher
By far the easiest way to sterilise glass jars is to run them through a dishwasher. Use a hot wash. You can run the lids through this too. The only issue with this method is that most of the time you need to have the jars hot when you’re ready to fill them. So, you need to time your dishwasher cycle to ensure the jars are hot and dry when you need them.
How to Sterilise Glass Jars in the Oven
I don’t have a dishwasher or microwave so I always use the oven method to sterilise my glass jars.
First turn your oven on to 140℃ (275℉, Gas 1). Then wash your jars in warm soapy water. Rinse them well, but don’t dry them. Instead place upside-down on a rack which fits inside an oven tray. Pop the tray into the oven and leave for at least 15 minutes. Alternatively, line the oven shelves with baking paper and place them directly on the oven shelves. It’s best to keep them in the oven until you’re ready to use them.
How to Sterilise Glass Jars in the Microwave
I don’t have a microwave, so I’ve never tried this method. It’s best used for small batches.
First wash your jars or bottles in warm soapy water, then rinse. Ensure you’ve removed any labels. Place your jars in the microwave and blast them at full power for 45 seconds or until they’re dry.
Please be aware that microwaves are not suitable for metal-clip jars or metal lids.
How to Sterilise Glass Jars in a Water Bath
Place clean jars and metal lids in a large saucepan filled with cold water. Bring to the boil and simmer for ten minutes. Place the jars upside-down on a clean rack to dry. It’s best to shake bottles out than place them on their sides.
How to Sterilise Lids
If you want your preserves to keep for as long as possible, don’t use plastic lids. This is because you can’t sterilise them and they generally don’t have a very good seal. Metal lids are the way to go. Alternatively, use kilner type jars.
You can boil the lids using the water bath method as mentioned above. Alternatively follow the tip below.
Although I’d made plenty of preserves in my time, I picked up a few tips from Pam Corbin when I attended her preserving course at River Cottage. One of her top tips was to turn the filled glass jars upside down whilst they’re still hot. Don’t forget to attach the lids first. This not only sterilises the lid, but creates a better seal too. I don’t really like the messy lids this method creates, but I’ve tried it a couple of times and it seems to work.
Don’t put the rubber rings from your kilner jars in the oven. They will perish. Boil them instead, just as you would lids, but only for a couple of minutes.
Hints and Tips
- Make sure the preserves are hot when you fill the jars and that the jars are also still warm. If you put hot contents into cold glass, it’s likely to shatter. Likewise, if your preserves are cold, make sure your glass containers are also cold.
- Use a sterilised metal funnel to ensure you don’t get any mixture on the rim of the glass as this could cause spoilage. Either pour the contents in directly or use a ladle.
- Fill your jars to about one centimetre from the top and seal.
- If you don’t have lids that fit your glass jars, cover with wax discs, then tie a piece of cellophane securely over the top. I generally use an elastic band.
- Label your jars. If you’re anything like me, I have no idea what’s hiding at the back of my cupboard. I often have to open the jar before I can tell what’s in it. Not ideal when you’re after chutney and you get jam.
- Store in a cool dark place. Most preserves will last for at least six months and generally longer if unopened. But check the recipe you’re using for details on this. Once opened store in the fridge.
- Discard any preserves that show signs of deterioration.
Some Recipes for Various Preserves You Might Like
Jams & Jellies
- Apricot & vanilla jam via Tin and Thyme
- Chocolate blackberry jam via Tin and Thyme
- Fig, apple & pomegranate jam via Tin and Thyme
- Greengage & apple jam via Farmersgirl Kitchen
- Hedgerow jelly via Tin and Thyme
- Persian carrot jam via Tin and Thyme
- Pumpkin & ginger jam via Fab Food 4 All
- Quince jelly with optional apple and chilli via Tin and Thyme
- Plum & chocolate spread via Jo’s Kitchen Larder
- Seville orange marmalade via Farmersgirl Kitchen
- Strawberry jam (no pectin) via Tin and Thyme
- Tomato chilli jam via Simply Sensational Food
- White currant jelly via Farmersgirl Kitchen
Fruit Curds & Butters
- Apple butter via Something Sweet, Something Savoury
- Blood orange curd via Tin and Thyme
- Cranberry curd via Fab Food 4 All
- Lemon curd with gin via Crumbs & Corkscrews
- Raspberry & rose curd via Tin and Thyme
- Baby tomato & sweet pepper chutney via Fab Food 4 All
- Beetroot chutney via Tin and Thyme
- Rhubarb & ginger chutney via Tin and Thyme
- Runner bean chutney via Greedy Gourmet
- Spiced apple chutney via Tin and Thyme
- Blackcurrant vinegar via Tin and Thyme
- Carrot pickles via Tin and Thyme
- Courgette & shallot pickle via Lost in Food
- Cranberry sauce with orange & port via Tin and Thyme
- Pam’s piccalilli via Lost in Food
- Spiced pickled beetroot via Tin and Thyme
Cordials & Syrups
- Dandelion honey via Tin and Thyme
- Rhubarb cordial via Jo’s Kitchen Larder
- Rose syrup via Tin and Thyme
- Mulled Pears via Lost in Food
Stay in Touch
Thanks for visiting Tin and Thyme. Let me know if I haven’t answered any of your questions on how to sterilise glass jars. Also, if you have any top tips on this subject, please do mention them in the comments below.