With strawberry season in full swing as I type, I thought I would share my recipe for canning strawberry jam using less sugar. But first, let’s quickly list the things you can do with your strawberry bounty: fresh eating, freezing for later use, dehydrating for later use, baking for now, strawberry syrup and freezing the excess, jams and jellies, of course don’t forget mashing and freezing in popsicle molds. Now let’s talk about canning jam.
Have you ever noticed when you hear of someone preserving strawberry jam, it’s always FREEZER jam? Why is it that you can easily find canning jelly recipes, but when it comes to canning strawberry jam, it’s not as easily found. Of course, you can find it if you use the recipe that calls for full sugar such as the yellow box of Sure-Jell pectin, but what about canning strawberry jam using LESS sugar as in using the pink box of Sure-Jell pectin? Well friends, I will be sharing with you today the process of CANNING strawberry JAM using LESS sugar!
First a disclaimer. Because I couldn’t find this recipe on Sure-Jell’s or Ball’s canning website, I sort of merged the instructions for using Sure-Jells pink and yellow pectin box and Ball’s strawberry jam canning recipe, did some math and this is what I came up with. There’s your disclaimer.
Now let’s can some jam.
Please note, towards the end of this article, I will have relevant, helpful short videos linked for you. Especially if you are new to canning, these videos will help.
STEP 1: PREPARE YOUR FRUIT
When canning strawberry jam using less sugar, the first thing to do is to prepare your jars and your berries. (The printable recipe card attached below goes over how to prepare your jars.) This recipe will give you 9 half pints or 18 quarter pints. For that you'll need between 3-4 quarts of fresh, ripe, whole strawberries. Do not use mushy or rotten berries. The quantity varies due to the size of the berries. Once you have collected your berries, dunk them in a sink of cold water; I like to add about 1/4 cup apple cider vinegar to the water and rinse the berries, 1 quart at a time. After rinsing, place the berries in a strainer to drain off the water. Once all berries are rinsed, use a knife and remove the green tops. My berries were homegrown, so they're not quite as big as store bought, which means, my berries do not have a tough or large core, so I did not have to core or hull my berries, but if your berries have a tough core, be sure to remove that. Place the prepared berries in a single layer in a shallow dish such as a glass pie plate like I used. Then use a potato masher and mash the berries to release the juices but also to give you bits of berries for your jam. Then pour the mashed berries, juice and all, in a measuring container. You'll need a total of 7 cups mashed berries, mashed berries and juice, for this recipe. Then pour the measured mashed berries and juice into a heavy bottomed 5-6 quart pot; I used my dutch oven pot.
Step 2: MIX IN AND BOIL
The second step in canning strawberry jam using less sugar is to measure and set aside your sugar in advance. Let's talk about the amount of sugar for a moment. When using the pink box of Sure-Jell pectin, we're actually using 3 c. LESS sugar than what their yellow box of pectin calls for. For this recipe, measure and set aside 4 cups of white granulated sugar. (For this recipe I have only used white granulated cane sugar, but if you want, I see no reason you could not use the light blonde more raw cane sugar. I have used that sugar in my other jelly recipes, and it's always worked just fine, I believe it would work just fine in this recipe as well.) Once you have your 7 cups of mashed berries and their juice, whisk in 1/2 tsp. butter, 4 Tbsp. bottled lemon juice, and 1 box of Sure-Jell Premium Fruit Pectin for Use in Less or No Sugar recipes, currently this is Sure-Jell's pink box. Do NOT add in the sugar yet. Once you have those 4 ingredients whisked together, set your pot on the stove and turn on high heat stirring often to prevent sticking and scorching. Bring the mixture to a rolling boil. A rolling boil is a boil that does not stop even while being stirred. Once the mixture comes to a rolling boil, quickly move on to step 3.
STEP 3: ADD SUGAR AND BOIL
The third step to canning strawberry jam using less sugar is once your mixture comes to a rolling boil, immediately dump in your pre-measured 4 c. white granulated sugar, all at once, and stir constantly to prevent scorching and sticking. Keep the heat on high the entire time. Allow the mixture to come back up to a boil, and allow it to be at a rolling boil for 1 minute, again stirring constantly. It needs to have this 60 seconds of a hard rolling boil. Once it has had a hard rolling boil for 1 minute, turn the heat off, and remove the pot from the stove and proceed to step 4. (Below I will have a short video on a rolling boil, actually recorded making this very recipe.)
STEP 4: FILLING JARS
The fourth step to canning strawberry jam using less sugar is to actually fill those jars! Lift the elevated rack out of your water bath canner and hang it on the sides of the canner. Then remove a half pint or quarter pint jar, your choice of what size you use, from the hot water bath canner dumping the water that was inside the jar back into the canner. (Again, instructions on preparing your jars are in the printable recipe card attached below.) Place the hot jar on a towel using a funnel, ladle some hot jam into the jar filling the jar but leaving 1/4" headspace.
STEP 5: REMOVE TRAPPED AIR
The next step to canning strawberry jam using less sugar is after filling the jar, remove any possible trapped air bubbles even if you do not see any, use something such as a chopstick to slowly swirl around inside the jar a couple times. Note at this stage the jam will not be thick; it will thicken and set once it has been canned and left to cool.
STEP 6: MEASURE HEADSPACE
Step six of canning strawberry jam using less sugar is to measure the headspace after filling your jar with jam and after removing any trapped air. If you do not have a headspace measuring tool, use a tape measure. I actually did this my first several years of canning, but as a generality, starting at the top of the jar mouth and working your way down, I have found that the BOTTOM of where the screw thread on the jar STARTS is 1/4", and the BOTTOM of where the screw thread ENDS is 1/2". After using the tape measure for a long time and before getting the handy green headspace measuring tool, I just went by the screw threads on the jar to judge my headspace. As I said, that's a generality, I cannot say that will work for all brands of jars as they could be made differently, but so far that is what I have found.
STEP 7: WIPE JAR MOUTH
The seventh step to canning strawberry jam using less sugar is to wipe the mouth of the jar. After filling the jar with jam, it's quite possible that jam will have gotten on the mouth of the jar, so use a damp cloth and wipe that mouth and screw threads well! Leaving any residue on the jar mouth will cause your jars to fail to seal. The lid seal and the jar mouth need to be clean and free of any debris of any kind in order to have a complete contact and proper seal. Please do not simply go through the motions of wiping the jar mouth off, but also look as you're wiping the jar mouth.
STEP 8: PLACE THE LID AND BAND ON
When canning strawberry jam using less sugar, do not overtighten the band when preparing the jar for the canner. Once your jar mouth is wiped off, remove a lid from your bowl of hot water and lids, I like to quickly pat the lid off, then center the lid on the jar. Use a band, some people call them rings, and tighten the band down on the jar to ONLY fingertip tight. Do NOT crank down on the band, do not use your wrist. Use only your fingers. (Below I will have a short video on fingertip tight.) Once your lid and band are on the jar, carefully place the jar back in the elevated rack being sure NOT to tilt them as doing so can cause jam to seep between the lid and jar mouth preventing a seal. Then continue until all jars are filled and back in the rack.
STEP 9: PROCESSING TIME
Nearly the final step when canning strawberry jam using less sugar is to actually process the jars! How exciting, we're almost there. One step closer to the fresh summer goodness smothering your flaky biscuits or poured over your fresh hot pancakes or drizzled over your yogurt or ice cream. YUM! With all jars filled with jam and back in the rack, lower the elevated rack back down into the hot canner making sure that water covers the tops of the jars by at least 1" no more than 2". (You may notice in this photo that I have a mixture of quarter pint and half pint jars, that is just fine. Feel free to mix these two sizes for this recipe. They both get the same processing time.) Once the rack is lowered back into the canner and the jars are covered with enough water, put the lid on the canner and turn the heat up to high. Once the water in the canner is boiling, set the timer for 10 minutes, leaving the canner on high the entire time. After 10 minutes, turn the heat off, leave the canner in place, remove lid, but do NOT remove the jars. Set the timer for 5 minutes. After 5 minutes, carefully remove the jars, one by one, placing them on a towel or elevated rack on the counter being sure to NOT tilt them as doing so could cause jam to seep between the lid and jar mouth and cause seal failure. Yes, there will be water standing on top of the lids, that's ok, it will evaporate off. Once all the jars are out of the canner, do NOT touch or move them for 12-24 hours. They need to completely come down to room temp and cool 100% for them to actually seal. After 12-24 hours, check the seals, if they have sealed, remove bands, wipe the jars, label, and store in a cool, dry, dark place. (A video will be linked below on how to test the seals and instructions are also given in the printable recipe card attached below.) That is it! You did it, you just canned strawberry jam using less sugar! Now enjoy it.
HELPFUL VIDEOS:
Below are three videos mentioned in this article. If you would like to see more canning videos, here is my playlist.
AGH Canned Strawberry Jam Less Sugar
Ingredients
- 3-4 quarts fresh, ripe, whole strawberries (no mushy, soft, or rotten berries)
- 1 (1.75 oz or 49 gram) box Sure-Jell Premium Fruit Pectin for use in less or no sugar recipes
- 1/2 tsp. real butter
- 4 Tbsp. store bought bottled lemon juice
- 4 c. white granulated sugar
Instructions
- In hot soapy water, wash and rinse 9 half pint or 18 quarter pint glass canning jars, lids, and bands. Be sure you have inspected your jars, lids, and bands for any damage. Do not can with chipped or cracked jars. Place lids in glass bowl and cover with hot water. Dry bands and set aside. Fill water bath canner about half full of water then add clean jars into the canner, using the water in the canner to fill the jars. Sit the jars on the rack inside the canner. Cover with a lid and turn on medium high heat. Prepare a kettle of water to contain hot boiled water to have on hand if needed.
- Fill sink with cold water and about 1/4 c. apple cider vinegar. Quickly rinse strawberries in the cool water, 1 quart at a time. Remove from water and place in strainer basket. Continue until all berries are washed.
- Cut off tops from berries and place prepared berries in a single layer in shallow dish such as a glass pie plate. Use a potato masher or fork to mash the berries and to release the juices. Place the mashed berries in a heavy bottom 5-6quart pot. Continue until all berries are mashed and in the pot; you need 7 c. mashed berries and juice. 3 quarts of berries should be enough, but if the berries are quite small, you may need closer to 4 quarts of berries.
- Whisk in the lemon juice, butter, and the box of pectin with the mashed berries.
- Measure out the 4 c. sugar and set aside.
- Place pot on stove, turn on high heat and bring to a full rolling boil, stirring frequently to prevent sticking and scorching. Use a spoon such as a wooden slotted spoon and with the berries at a full rolling boil, dump in all the sugar, all at once, and continue stirring. Keep your heat on high. Keep stirring and allow the berries to come back up to a boil, once they are at a rolling boil again, keep stirring for 1 minute; let them boil hard at the rolling boil for 1 minute while constantly stirring. A rolling boil is a hard boil, it's a boil that cannot be stirred down. As in it continues to bubble and boil even when being stirred.
- After the 1 minute of hard boil, turn the heat off and remove the pot from the stove. Skim off any foam.
- Lift the elevated rack and hang it on the sides of the canner. Dump the water in the jars back into the canner. Using a funnel and ladle, fill each jar with the strawberry jam leaving 1/4" headspace. Use a chop stick or something to slowly make a couple swirls in the jam inside the jar to release any possible air bubbles then remeasure the headspace adding more jam if necessary. At this point, the jam will be runny, it'll thicken once canned and cooled. Wipe the rim of the jar mouth with a damp cloth being sure to clean the mouth completely. Quickly pat dry a lid and center the lid on the jar. Then use a band and tighten the lid down to fingertip tight. Fingertip tight is when you screw the band down just until you feel resistance then screw it a quarter turn more using ONLY your FINGERTIPS. Place jar in canner and continue until all jars are filled.
- Lower the elevated rack into the canner. Ensure that water is covering the tops of the jars by at least 1". Add more boiled hot water if necessary. Then bring the heat up to high. Cover with the lid and let it boil.
- Once the water inside the canner starts to boil, set the timer for 10 minutes, leaving the lid on and the heat on high the entire time.
- After 10 minutes, turn the heat off, remove the lid, but do NOT remove the jars. Set the timer for 5 minutes.
- After 5 minutes, carefully remove the jars from the canner and place on an elevated rack or a towel on the counter. Be careful not to tilt the jars, as doing so can cause the jam to seep between the jar mouth and lid and prevent a seal. Yes, there will be water on top of the lid, it's ok; it'll evaporate.
- Once all the jars are out of the canner, leave them alone for 12-24 hours. Do not touch or move them during that time. This ensures they will be completely cooled and have sealed.
- After 24 hours, check the seals. To see if the jars are sealed, press your finger onto the center of each lid. If there is no flex and it doesn't give, remove the band. Then using only your fingertips, grasp the outside of ONLY the lid and lift. If the lid does not separate from the jar, it is sealed. Then wipe down each jar and label.
- Store without bands in a cool, dry area away from heat and light as this will help them retain their color and nutrition longer.
- If any jars did not seal, store those in the fridge and use first or immediately re-process those jars using a new lid and checking the jar mouth for damage.
Notes
If you have any questions about canning such as how to prepare for canning; how to know if your home canned food is safe; how to test your seals and more, check out my playlist. https://youtu.be/_OWxo8_mJl8?si=kSXRn4OWZgavJlA6
