Canning Strawberry Jam

4.92 from 12 ratings

Canning strawberry jam is a delicious, low-sugar, and fresh-tasting spread for toast, yogurt, or dessert recipes. Homemade strawberry jam is an amazing way to preserve the harvest and is a treat for the whole family.

Prep Time20

Cook Time20

Canning Time10

Total Time50

Course: Canning

Cuisine: American

Keyword: canning strawberry jam, homemade strawberry jam, making strawberry jam

Servings: 8 oz jars

Author: Sarah Cook

Equipment

Ingredients

8 cups strawberries {tops removed (~4 pounds)
2.5 tsp Pomona's Pectin
2.5 tsp calcium water {from Pomona's Pectin box}
1.5 cups sugar
1/4 cup bottled lemon juice {do not use fresh}

Instructions

Prep for the canning part

Prepare water bath canner by filling it with water, and setting it on the stove. Turn the burner to high. Once it reaches a boil, reduce it to simmer. You want to keep the water hot so that everything is ready when the jam is.
Wash and sanitize your jars. You can fill them with hot water, or place them on a tray in the oven at 170˚F degrees.
Wash your lids and set aside in clean place.

Making Strawberry Jam

Rinse the strawberries. Remove the tops and cut in halves or quarters (8 cups total). Place in a heavy-bottomed saucepan.
8 cups strawberries
Heat the fruit over medium heat until the juices start to bubble. At this point, you can mash the fruit with a potato masher, or use an immersion blender (only blend ~30% of berries).
In a small bowl, combine 1/2 tsp calcium powder (comes in the box of pectin) with 1/2 cup cool water.
In a separate bowl, combine sugar (1.5 cups) and pectin (2.5 tsp). Set aside. To prevent clumping in the fruit, Pomona's must be mixed with your sweetener before being added to the fruit.
1.5 cups sugar, 2.5 tsp Pomona's Pectin
Add the lemon juice (1/4 cup) and calcium water (2.5 tsp) to the pot with the strawberries, stir.
1/4 cup bottled lemon juice, 2.5 tsp calcium water
Add the sugar/pectin mixture, and bring to a rolling boil. Stir constantly for 3 minutes, turning down the burner to medium if the jam starts popping.
At this point, turn the burner under the canner back up to high and get that water boiling again.
Remove the jam pot from heat, and stir gently for 5 more minutes. At the end of the 5 minutes, skim any foam that remains.
Using the funnel and a ladle, add the jam to your prepared jars, leaving 1/4 inch of headspace at the top. Headspace is the amount of room between the top of the food, and the top rim of the jar.
Using a wet clean rag, wipe the rim to make sure there isn't any sticky jam on there.
Place a new clean lid on the jar and then a ring. Tighten the ring to fingertip tight.
Using canning tongs, add jars to the boiling water, and put the canner lid on. Pro tip: you must have at least 1 inch of water over the tops of the jars for safe canning.
Process half-pints and pints based on the elevation guide below:
*0-1,000 ft – Half-Pints & Pints =5 min
*1,001-6,000 ft – Half-Pints & Pints =10 min
*6,000 ft+ – Half-Pints & Pints =15 min
Once the jam has processed for the appropriate amount of time, remove the canner from the burner, and carefully remove the lid of the canner (Pro tip: use oven mitts to take the lid off because the steam is super hot).
Using canning tongs, carefully remove the jars, and place them on a thick towel in a place where they can be undisturbed for 12 hours.
After the jars have rested for about 12 hours, press down in the middle of each lid. If it "gives" at all, the jar didn't seal. Either enjoy it that day, put it in the fridge, or reprocess it.
Once the jars have sealed and cooled, remove the rings. Label and store sealed jars in a cool (best results are 50-70˚F) dark place for up to 12-18 months.

Notes

Makes 5, 8 oz jars.
8 cups fresh strawberries generally equal about 5 cups of mashed berries.
Jam is best when made in small batches. Avoid doubling or tripling the recipe.
Will last for 2-3 weeks in the fridge or 12-18 months sealed and at room temperature.
Nutrition values are an estimate only

Nutrition