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.
Rubber Rings
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
Chutney
- 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
Pickles
- 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
Other
- Mulled Pears via Lost in Food
For more inspiration take a look at some of the other recipes in my Preserves category. And for even more ideas, head over to my Fermented and Preserved board on Pinterest.
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.
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Choclette x
Alida@mylittleitaliankitchen.com says
Thank you for these tips. Really useful. My mum makes lots of tomato sauce and jams in the summer because she has a field with tomatoes and a few fruit trees. I would love to make more jams, they are far less sugary and they taste better than the shop bought ones.
Choclette says
Your Italian home always sounds fabulous Alida. I expect there’s a lot of hard work too, but how very satisfying to be able to make so much of your own tomato sauce. AND it’s a very rare thing indeed for me to buy commercial jams. As you say, far too sweet.
Nayna Kanabar says
I did not realize how important it is to sterilize the jars properly. Reading this post has certainly made think I should be more diligent and ensure that I follow this process.
Choclette says
It’s always best to err on the safe side when it comes to preserving hygiene. Especially if they are going to be given away.
sherry says
i always use the hot soapy wash then into the oven for about 20 minutes method. Of course living in Queensland it’s best to keep most foodstuffs in the fridge so any preserves etc go straight into the fridge. and they last for a very long time!:-) cheers sherry
Choclette says
I take it you have a very large fridge Sherry? The last couple of summers have been really hot over here, so I’m hoping it’s a blip and we don’t have to go down the fridge route.
angiesrecipes says
Choclette, this is such a wonderful and educational post. A very important step in preserving.
Choclette says
Thank you Angie. It is an important step, but not an obvious one if you’re new to preserving.
Jo Allison says
Such a useful post Choclette. Oven method is also my go to when it comes to sterilising! Thank you so much for including my recipes!
Choclette says
Thanks Jo. I think the oven method is the most common. It’s the easiest to control anyway.
Chloe Edges says
Really interesting Choclette, I didn’t know you could sterilise in the microwave either!
Choclette says
It’s amazing the things you learn doing this blogging lark.
Janice says
This is so useful. Thank you for including links to my recipes.
Choclette says
I’m always having to look up the oven temperature, so I will definitely find this useful.
CAMILLA HAWKINS says
Every good preserve depends on a thoroughly sterilised jar so a great post to share. Thanks for sharing my preserves:-)
Choclette says
Yes indeed. I hate having to throw away food and I certainly don’t want to poison anyone.
Michelle Rolfe says
Great post Choclette, I always still worry and double check about sterlising before I start any jam or jelly as I don’t want to loose any. Thanks for including our recipes in your roundup as well. 🙂 Cheers, Michelle
Choclette says
It’s not at all fun if you have to throw away something you’ve made is it? I always have to check the oven temperature when I’m sterilising my jars, so I’ve glad I’ve got it down in an easy to find post – finally!