Low Sugar Blueberry & Raspberry Jam is a delicious fruity spread made with fresh or frozen blueberries and raspberries. It has two-thirds less sugar than traditional jams and jellies and is easy to make in a small batch. And is the perfect accompaniment to bread, croissants and scones.
Why make Low Sugar Blueberry & Raspberry Jam?
Low Sugar Blueberry & Raspberry Jam is a delicious combination of two popular fruits. I love to make jam and I also like to eat it, however it is generally very high in sugar. I’ve had a few comments about the high sugar content of my traditional jams so I thought I’d experiment and use less sugar.
This Blueberry & Raspberry Jam is packed with fruity flavour and you really don’t miss the sugar. You have to store low sugar jam differently but otherwise, you would be hard pushed to tell the difference.
How much less sugar is in Low Sugar Blueberry & Raspberry Jam?
This recipe has two-thirds less sugar than my traditional recipes. My traditional jam recipes usually have a similar weight of sugar to the weight of the fruit but my low jam recipe has one-third of sugar to the weight of the prepared fruit.
What ingredients do I need to make Low Sugar Blueberry & Raspberry Jam?
You need very few ingredients to make this jam, here are the ingredients you need:
- Blueberries
- Raspberries
- Sugar
- Lemon
What kind of blueberries should I use?
I use fresh blueberries as they are generally easily available all year round and the price is fairly stable. However, you can use frozen blueberries without changing the recipe.
What kind of raspberries should I use?
I use frozen raspberries because they are generally less expensive and I always have a bag of frozen raspberries in the freezer. It doesn’t matter if they are a bit broken because they will break down in the jam anyway. If you have fresh raspberries they will make excellent jam too.
What kind of sugar do I need to make low sugar jam?
I use granulated white sugar and this works perfectly for jam to eat at home. If you plan to enter a competition with your jam, buy specialist preserving sugar. This type of sugar has larger crystals that dissolve more slowly and create a crystal clear jam with less froth on top. Jam Sugar which has added pectin and gelling agents is not suitable for this recipe.
Do I need to add pectin to the jam?
Pectin is the ingredient that makes jam set or gel. I use lemon juice in this low sugar jam because lemon juice helps the pectin strands to come together and set the jam so there is no need to add extra pectin. As lemon juice is highly acidic it also helps to reduce the growth of bacteria.
How do I store Low Sugar Blueberry & Raspberry Jam?
Store the jam in the fridge. High sugar jam will keep at room temperature as long as the jars are sealed and sterilised. However, low sugar jam would spoil at room temperature. You can keep the jam in a sterilised jar in the fridge for about 6-8 weeks. Although it is so good it is unlikely to last that long.
Can I freeze the jam?
If you don’t want to eat your low sugar jam straight away. Put the cooled jam into a small, clean freezer-proof container. You can keep it in the freezer for up to 6 months. To defrost, place the container in the refrigerator and defrost slowly overnight. Give the jam a stir and use it within a week of defrosting.
What does Low Sugar Blueberry & Raspberry Jam taste like?
It has a lovely fresh fruity flavour and you can taste both the blueberries and the raspberries Although low sugar jam has a softer set than traditional jam it does firm up in the fridge and it spreads well.
Can I make a larger batch of Low Sugar Blueberry & Raspberry Jam?
You can double this recipe for a larger batch of jam. I would not recommend making any more than double the quantity as it will make it more difficult to get it to the correct consistency.
Do I need to water bath low sugar jam?
This low sugar jam does not need to be treated in a water bath. Store the jam in a sterilised jam in the refrigerator and it will keep without spoiling for up to 8 weeks.

Why should I sterilise my jam jars?
It’s important to sterilise jam jars in order to eliminate any bacteria that may be in lurking in the jars. This bacteria could transfer to the jam and make it grow mould which would ruin all your work. I always sterilise my jam jars even for a jam that is stored in the refrigerator.
How do I sterilise jam jars?
- Carefully wash and rinse the glass jars and the metal lids
- Put the wet glass jars on a baking tray upside down.
- Put the baking tray and jam jars into the oven at 150C just as you start to make the jam. The water inside the jars will turn to steam which helps to sterilise the jars.
- Put the lids into a large heatproof jug or bowl and cover with boiling water from the kettle. Drain and lay out the lids to dry on kitchen paper.
- When your jam is ready take the jars out of the oven and fill them with hot jam, then put on the lids.
- When the jars have cooled check that the lids are tight and tighten further if needed.
You can also sterilise your jam jars on a hot wash in the dishwasher.
What is a rolling boil?
A rolling boil is a fast bubbling boil You need to get the jam to a rolling boil so that it will set. I had the advantage of watching my mother make jam to see a rolling boil. Check out this video to see what a rolling boil looks like.

How can I tell when the jam is ready?
The usual tests don’t really work for Low Sugar Jam. However, I use a test similar to the wrinkle test to check it is set. The jam will not wrinkle as much as it would in a high sugar jam. But if you push your finger through the jam on a cold saucer it should leave a clear space and not run back into the place where your finger has been.
Before you start to make the jam place 2 saucers or small plates in the fridge.
• After the jam has been at a rolling boil for 10 minutes, take it off the heat.
• Put a teaspoon of the jam onto one of the saucers from the fridge.
• Return it to the fridge for 5 minutes.
• Take the saucer out of the fridge and push your finger across the jam. If it is ready it will leave a clear space and not run back into the space where you pushed your finger (see photo above).
• If it is not ready, bring the jam back to a boil for 5 minutes then repeat the saucer test. Be careful not to burn the jam on the base of the pan.
• Skim off any froth on top of the jam in the pan with a metal spoon, then pour or ladle your jam into sterilised jars and seal.
Vegetarian
Low Sugar Blueberry & Raspberry Jam is suitable for vegetarians.
Gluten Free
There are no ingredients containing gluten in this low sugar jam recipe. If you are using canned peaches or including any other ingredient that is not fresh, please check the labels.
For more information regarding any dietary information provided on this website, please refer to my Nutritional Disclaimer.
How should I serve Low Sugar Blueberry & Raspberry Jam?
Serve the blueberry jam just as you would any other jam or jelly. I like to serve it on toast and a cup of tea! It’s also delicious served with scones, pancakes and croissants (crescent rolls). Why not serve a spoonful of jam with your breakfast porridge or on a bowl of Greek Yogurt?
Blueberry and Raspberry Jam is also the perfect accompaniment for my Air Fryer Blueberry Scones.
More Low Sugar Jam Recipes
PIN FOR LATER

Low Sugar Blueberry & Raspberry Jam
Ingredients
- 125 grams (1 cups) blueberries
- 125 grams (1 cups) raspberries
- 90 grams (0.5 cups) sugar
- 50 ml (3.5 tbsp) water
- 1/2 (1/2) lemon (juice only)
Instructions
- 125 grams blueberries, 125 grams raspberries, 50 ml water, 1/2 lemon (juice only)Put the blueberries, raspberries, water and lemon juice into a pan.
- Cook the fruit gently until it is soft.
- 90 grams sugarAdd the sugar and heat gently until it has dissolved.
- Bring to a rolling boil and boil for about 3-4 minutes, stirring occasionally to check that the jam is not catching on the bottom of the pan.
- When the jam starts to thicken, remove it from the heat.
- Check the set by putting a teaspoon of jam on a cold sauce and place it in the fridge for 5 minutes. Push your finger into the jam and it should leave a clear space in the middle of the jam.
- If it has not set then return it to the heat and cook for another minute or two.
- When your finger leaves a clear space through the jam on the saucer it is ready.
- Spoon it into a sterilised jam jar and seal with a lid.
Choclette says
This is a new one on me. I’ve never had blueberry and raspberry jam before and now I really want to try it. I bet it’s delicious.
Janice Pattie says
Thanks, Choclette. It is really delicious and a lovely combination of fruits.
Kacie Morgan says
Mmm, blueberry and raspberry sounds like a delicious combination for jam. I could just see me spooning it onto pancakes, and I love a dollop of jam in porridge too.
Janice Pattie says
Thanks, Kacie. It would be lovely with pancakes and in porridge.
Lesley says
What a lovely flavour combination and super clear recipe instructions too. I’d happily have a spoonful on a scone right now.
Janice Pattie says
Thanks, Lesley. It is definitely a great jam for scones.
Cat says
Blueberries and raspberries sound like the most delicious flavour combination! And less sugar is always a nice idea.
Janice Pattie says
Thanks, Cat. Absolutely.
nancy says
i love this jam that’s not sickening sweet! it is perfect!
Janice Pattie says
Thanks, Nancy. This is definitely just sweet enough.
[email protected] says
I’ll have to be trying this – what with my new found love of blueberries and all, it would be rude not to!
Janice Pattie says
Absolutely! I hope you enjoy it.