Low Sugar Strawberry Freezer Jam + Tips and Tricks to Setting Jam
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The fruity taste of strawberries really shines in this low-sugar strawberry freezer jam made easy in the microwave. Plus tips + tricks for setting jam!
One of the supermarkets in my area had a ridiculously good deal on strawberries. $3.99 per flat! For those who don’t know, a flat is 8 pounds of strawberries! I needed some fruit for a party I was having, but there was plenty to spare, so I decided to make some freezer jam.
LOW-SUGAR STRAWBERRY FREEZER JAM
I searched for a good recipe, and found some I liked, but was shocked about the amount of sugar in almost every recipe I found. I wanted a low-sugar strawberry freezer jam, so I decided to try and make it with less sugar.
At first, it was unsuccessful, which I am sure had nothing to do with the sugar and I will tell you why in a minute.
I ended up with jam that separated as soon as I poured it into my jars: fruit on top and liquid on bottom. I knew it wasn’t going to set, so I added more Pectin and re-heated my mixture, and it worked great.
THE SCIENCE OF SUGAR AND PECTIN IN JAM
Sugar draws liquid from fruits, which is also known as maceration.
When my low-sugar strawberry freezer jam was still runny after my first attempt, the fact that I used less sugar had nothing to do with it. After all, I had used less sugar, so hypothetically, there wouldn’t have been as much liquid drawn from the fruit, right?
Maybe or maybe not, but none of that mattered anyway because the sugar is not going to make a jam more thick or less thin; it’s not a thickening agent. The Pectin is the key thickener in jams.
Fruits naturally have Pectin, but the riper the fruit, the less Pectin the fruit naturally has. Strawberries are already lower on the Pectin spectrum.
Heat makes Pectin form into a gel. So when I added more Pectin and re-heated my mixture, the heat helped the Pectin gel up and it worked beautifully.
TIPS & TRICKS TO SETTING JAM
I am pretty confident in saying, if you have runny jam, extra Pectin (start with 1 Tbsp more) AND Heat will fix your problem.
Here is some Pectin, fruit, and jam science facts for you:
“When dissolved and let cool, Pectin forms invisible strands that hold liquid in. Acid (such as lemon juice) helps draw even more Pectin out of fruit when it is heated. Water is attracted to sugar. Adding sugar causes some water to be drawn to the sugar molecules, leaving the Pectin molecules free to more easily get at and bind with each other, setting the preserve.” (Source: http://www.cooksinfo.com/pectin)
So now that you know why you might be having problems with strawberry jam setting, you can go ahead & try this recipe! I hope it brings you success!
WILL THIS RECIPE WORK WITH OTHER FRUITS?
Yes! Just keep in mind the natural pectin in the fruit you are using and adjust the pectin as needed. Check out this pectin chart to help you. We’ve tried this recipe with strawberries and peaches.
MORE RECIPES TO USE UP FRESH STRAWBERRIES
- Strawberry Crisp – Fresh, juicy strawberries are topped with a buttery brown sugar and oat crumb topping.
- Strawberry Cream Pie – light, fruity, and delicious. With layers of pie crust, no-bake cheesecake, and slices of fresh strawberries smothered in a sweet glaze.
- Cheesecake Stuffed Strawberries – A super easy to make, no-bake dessert that is light, fruity and delicious. Low carb and keto friendly.
Low-Sugar Strawberry Freezer Jam
The fruity taste of strawberries really shines in this low-sugar strawberry freezer jam made easy in the microwave.
Ingredients
- 3 1/3 cups crushed strawberries (about 2lbs strawberries)
- 2 Tbsp lemon juice
- 6 Tbsp Ball Classic Pectin OR 3 Tbsp Low or No Sugar Needed Pectin (equivalent to about 1 box of other brand pectin)
- 1 1/2 cups granulated sugar
Instructions
- Wash, hull and crush strawberries in a LARGE (10 to 14-cup) microwaveable bowl to equal 3⅓ cups. You may use a potato masher, food chopper, or food processor to crush the strawberries; do not puree--leave slightly chunky. Add lemon juice and Pectin. Mix well. Let it sit at room temperature for 20 minutes.
- Add sugar; stir until mostly dissolved. Heat in the microwave on high for 10 minutes until boiling and foamy. (Keep an eye on it so it doesn't boil over.) Remove and stir one last time. Mixture will still be thin.
- Skim the foam off the top, then pour jam into clean freezer containers leaving ½-inch head space for expansion. Your jam should look consistently chunky throughout the jar after it is poured into the jars. If the fruit has risen to the top and the liquid remains at the bottom, pour the fruit back into the bowl, add one additional tablespoon of Pectin and heat again until boiling and foamy.
- Immediately top with lids and let stand at room temperature for 1 to 2 hours to cool down before placing in the freezer. Refrigerate up to 3 weeks or freeze up to 1 year.
- *To use freezer jam: Pull from the freezer, allow to thaw in the fridge, and use like store-bought jam. (The freezer is for storing purposes, since the jam was not canned in a hot water bath.)
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118 Comments on “Low Sugar Strawberry Freezer Jam + Tips and Tricks to Setting Jam”
Tried this yesterday & great recipe. I added 1 TBSP of Pectin (used Surejell) & added 1/4 cup of Truvia. My family likes it better than the full sugar recipe. You actually taste the fruit & not the sugar. Thanks for sharing!
That’s so great! Thanks for sharing your experience!
Can u use other fruit with it? I made it yesterday with low sugar pectin and it’s amazing
For sure! Go for it!
Just made this today! So simple! Think I’ll try it with peaches too. Or whatever fruit I have this summer. Big thank you for this super easy, heat friendly recipe.
Ooh peaches sound like a great idea! Glad you liked the recipe!
Is the lemon juice really necessary, and if so, why?
It might help add a little bit extra natural pectin and it does add a little taste, but you can definitely leave it out if you want to.
Hi there! So excited to find a low sugar recipe. Can you tell me how long it should take for the jam to “set up”? Should it be firm before putting it in the freezer? I’m afraid I will need to boil it again 🙁
If you pour it into the jar and it separates (fruit on top, liquid on bottom) you definitely need to add more pectin and re-boil. It will set more as it cools, but as long as the mixture has a good consistency and doesn’t separate it should congeal properly after it is completely cool.
I made 2 batches and they worked great! Second batch I had to repeat step 3 and boil after adding 1 more Tbsp. pectin. Love that you taste strawberry and not sugar! Thank you, amazing recipe! Love learning the science behind the recipe!
**Do you know of adaptations for other fruit jams? Strawberry-Rhubarb? Raspberry? Mixed berry? Peach?
Great news Sarah! This recipe should work for most fruits. You may need to adjust the additional pectin depending on the level of natural pectin in the fruit. I found this chart helpful to know which fruits are naturally high/low of pectin: http://www.kilnerjar.co.uk/acidity-and-pectin-chart
I’d love to hear if you do try it with other fruits! Good luck!
This looks really good, and judging by all the comments, is good! I have been looking at freezer jam but was worried about the sheer quantity of sugar required.
I would love to have a go but here in the UK we use different measures: weight not volume. Have you any idea how I can convert this to lbs and oz?
I am dying to try it and am going out right now to buy some pectin. Not sure about the different brands, but I’m assuming they will be roughly equivalent?
Hi Jenni,
Try this, I hope I converted everything right:
2 pounds of strawberries.
2 Tbsp lemon juice is 1 ounce.
6 Tbsp of pectin is about 1.75 ounces.
1 1/2 cups sugar is about 10.65 ounces.
Good luck!
I haven’t read through all the comments but would your low sugar method work with other fruits? Raspberries, blueberries, haskaps, wild low and high bush cranberries and blackberries?
In most cases, yes. The sugar doesn’t effect the ability to make jam set, it just makes it sweeter. The natural pectin found in a particular type of fruit might effect the jams texture though. Some fruits have less pectin than others, so you may have to adjust the quantity of the pectin you add to it. Just google “fruit pectin chart” and you should be able to find good info on how much pectin fruits naturally have in them to give you an idea on how much additional pectin to add.
This is the BEST strawberry freezer jam I have ever tasted! Better than high-sugar. Do you have a recipe for low-sugar raspberry jam or can substitute the raspberries straight across?
Hi Jackie! So glad you like this recipe! You can absolutely swap fruits. Just keep in mind the natural pectin of the fruit and adjust the additional pectin as needed. Raspberries should work just like the strawberries with no additional adjustments. Enjoy!
Ok – I made the regular freezer jam last night ( I did question the amount of sugar in my mind) and checked it today to see how it set up. It set up ok but oh my aching sweet tooth – TOO sweet! Plus the sugar didn’t dissolve all the way. Is there any way to salvage this? I have more berries – my thought was to get some of the low sugar pectin add some more lemon juice and put the whole mess in a pan on the stove. Can the 2 different pectins be used together (the one I used was liquid for freezer jam – Certo)? Or maybe just make a new batch with the berries left. 22 pint jars of jam is a lot to throw away.
If the sugar didn’t dissolve you definitely need to cook it longer. It needs to boil and dissolve completely, but don’t overcook it either. If you are doing a big batch, make sure to use several pots so it heats evenly. You can add more fresh berries to try and thin out the sweetness and definitely try more pectin and a little more lemon juice. I’m not sure about mixing the two pectins together though. Good luck! Here’s a great article that may help you: http://www.pickyourown.org/pectin.htm
Wow! Thanks for the fast reply, truly appreciated! The pectin I used didn’t call for heating on the stove, just mix for 3 mins with the lemon juice. I did check a couple of other jars and the sugar doesn’t seem to be a problem ( the one I tasted was from the jar of a little left over from batch to batch) but the sweetness – UGH. It’s been about 8 years since the last time I made any and I don’t remember it being this sweet, nor my Gma’s (40 yrs ago). I’m going to go with your suggestion of more berries, pectin and lemon – that makes sense to me. Again thanks for the quick reply – you have probably saved 22 jars – I think I hear some clapping from the kitchen.
I love your recipe , I have made peach too , on the stove top and it is great , I would like to try pineapple with a hot pepper minced in with it , is pineapple a high pectin fruit ? Do you have a recipe for something like that , I love the low sugar in the recipes
Hi Sandy, I bet this would work for pineapple too. It’s low in pectin like strawberries, so I’m betting you won’t have to adjust anything. Good luck!
A few years ago there was a recipe for low sugar. It only used 2 cups of sugar. It always turned out fine. About two years ago they changed the recipe. It did not turn out the same. It set but it separated. This year the recipe is not on the sheet. They only have the box with the artifical sweetner now. Does anybody remember this? I wonder why they stopped the recipe,because it always worked good. This was on the Pecton box. Doesn’t cooking the strawberries change the color of them to a darker color?
It’s always upsetting when they change the directions on the box. My recipe has worked well for many people. Cooking the strawberries doesn’t darken them very much, as you can see the final product in the pictures of this post. I hope you’ll give my recipe a try.
Hi! I’m making this today but need to make sure I have enough jars 😉 do you happen to know how many jars/containers it made for you? And their sizes? Thank you!!!!
Hey Morgan,
I tried leaving a comment yesterday from my phone, but I see that it didn’t work. Hopefully you had what you needed. It made 5-6 (8oz) jars for me. I’ll add that to the recipe card.
It’s been a long time since I have made this recipe….I used 8 oz jars and I think it made somewhere between 6 and 10 jars. I now use Ball RealFruit Instant pectin. It uses about the same ratio of sugar to berries. It only takes 30 minutes and noooo cooking!
Wow! Will have to try that instant pectin! Thanks Linda!
Thanks for such a detailed and well-written recipe! I was forced to buy low sugar pectin because the store didn’t have the regular, and it was hard to find a recipe that listed specific amounts to help me use it for freezer jam (first timer here, so not a lot of confidence in improvising). Tried it this morning and it was great!
Glad I could help! So happy you enjoyed this recipe!
I just made this tonight and I was quite surprised as I only got 3, 8 oz jars after skimming the foam… Did I do something wrong? It certainly was easy to make!
Hmm. That’s a bummer. Maybe your was just extra foamy.
Last summer I stumbled upon your recipe and made several batches of strawberry. Using the same ratios of crushed fruit and pectin also made blueberry and peach. My previously non-jam eating kids finished it all up over the winter and begged me to make more as fruit came into season this summer! I almost cried when I couldn’t find your recipe when it was jam making time. It’s now safely pinned, printed, and saved. I’m excited to make all of the above flavors again and try plum this year, too!
I’m so glad you were able to find the recipe again and that it’s working out with so many different fruits! Yum! Thanks for your comment Kris!
Just remember it’s going to take longer if you double the recipe. Mine did not boil in 10 minutes. Also factor in the strength of your microwave. Thank you for the 3 min hard boil suggestion.
Yes, thanks for pointing that out!
I looked everywhere online for low sugar cherry freezer jam but couldn’t find anything. I decided to give this recipe a try. Used black cherries and followed your recipe using one package of sure jell original. I found I had to add two tbsp water but it all came out great! Had to follow your advice about adding 1 T more pectin and reboiling but it worked out great. I’m over the moon with my cherry freezer jam, it’s sweet / tart, just like I wanted. Thank you!
That’s great! So glad you could tweak this recipe with the cherries!
I made this recipe with black cherries and it came out great. I found I had to add 2T water because my cherries weren’t as juicy as strawberries. Hope this helps.
For blueberries, a pectin chart shows they have more pectin than strawberries. No need to add less in the recipe? I was also wondering about the skins of the blueberries. That may sound silly, but should it be chunky with the skins or won’t that happen after mashing and cooking? Planning to try tonight.
You can absolutely use less added pectin since the blueberries naturally have more in the fruit itself. If for some reason it doesn’t thicken, you can always add more pectin and bring the mixture to a boil again. As for the skins of the blueberries, it will be chunky. The skin holds the pectin and blueberry flavor. Mashing it or pureeing it, might help some.
I used the same proportions to make this recipe with blueberries and it wasn’t too thick. I only slightly squished my berries so that the juice squished out because we like it chunkier. There were squished but intact berries throughout.
I have made this freezer jam many times and it turns out perfect every time. I really like that you can taste the strawberries and not just “sugar”. I cook mine on top of stove with no problems.
I’m so glad that you are enjoying this recipe Lori! Thanks for your comment!
Delicious! First time to make jam and I followed the recipe exactly except I cut back the lemon juice to 1.5 TBSP. It turned out great! I have another big bag of strawberries left and I might even try it with just 1 c. of sugar because my berries are fresh out of the patch and pretty sweet already. Excellent recipe!
Wonderful! Thanks for your review!
This is the third time I’ve made this jam and it’s wonderful! It actually tastes like strawberries! So quick and easy. My family absolutely loves it!
Thanks for sharing your review Mesa! I’m glad to hear you are enjoying this recipe!
My daughter Eliza taught me how to make this recipe for jam. We are so pleased that the sugar to berry ratio is so low. Today I made it on my own – it is easy and quick – and the result is fantastic!!! I had 3 pint jars full! I love how the reduced sugar allows the strawberry taste to be front and center! Thanks Amber! Our best to you and Kyle and your sweet ones!
Hi Rebecca! Thanks for stopping by my blog! I’m so glad you enjoyed this recipe and thanks for the well wishes!