Low Sugar Blackberry Jam (No Added Pectin, with a Seedless Option)

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Lately, I've been trying to empty the freezer by freeze drying meats, stock, and veggies. (It's SO easy! I love this method of preservation!) But I had quite a few bags of blackberries in the freezer - wild blackberries we picked by the bucketfuls last summer. I'd set them aside for pies, crisps, and jam-making, simply by throwing them in a Ziplock bag and dumping them in the freezer. I didn't really want to freeze dry clumps of berries, so I decided I'd better use my canning kitchen as a canning kitchen (for the first time!) and whip up some jam.

But do you know how much stinkin' sugar is called for in traditional blackberry jam? Holy smokes! More sugar than berries! That just won't do, around here. I could have ordered some Pomona's Pectin (which allows you to customize the amount of sugar you use, unlike typical store bought pectin), but I wanted to can right away. I also could have used one of a myriad of "no sugar" blackberry jam recipes found online...but they aren't truly sugar free. They use juice or honey...which is still sugar. I also could have cooked the jam on the stove top and made freezer jam, using only enough sugar so my kids liked the jam. But I was trying to empty the freezer.

So I decided to make blackberry jam the old fashioned way. You see, blackberries contain natural, so adding pectin is unnecessary. However, in order to get no-added-pectin blackberry jam to gel, you gotta cook it down more than you would if you used store-bought pectin. This means your berries won't make as much jam...but I'd rather have fewer jars of jam that are low in sugar than more jars of jam and that have crazy amounts of sugar.



No Added Pectin, Low Sugar Blackberry Jam

Another bonus to making jam the old fashioned way is that you can double, triple, or otherwise expand the recipe without fear of the jam not setting!

2 cups crushed blackberries (wild or domestic)
Granulated cane sugar
2 teaspoons bottled lemon juice

1. Pour the blackberries in a heavy-bottomed pan. (Lightweight pans will scortch your jam.) Add sugar, to taste. (I used 1 scant cup of sugar. I recommend starting with less sugar than you think you need; then taste and add more sugar if needed.)

2. Place the pot over medium high heat and stir until the sugar is completely dissolved.

3. Stir in the lemon juice. (Because the lemon juice adds acidity, it makes mold and bacteria less likely to grow in the jam. Use bottled juice, which has a standard acidity, instead of fresh juice, which could be less acidic.)

4. Boil and stir and boil and stir and boil and stir until the jam is thickened. The best way to know when the jam is done is to use a good  thermometor.* When the jam reaches 220 degrees F. (at sea level; click here for temps at higher elevations), it's done. If you don't have a thermometor, all is not lost! Use the "sheet test" or the "freezer test," as described at The National Center for Home Food Preservation website.

5. Ladle jam into hot 4 or 8 oz. jelly jars, leaving 1/4 inch headspace, and process in a water bath canner for 10 minutes. (If you live at a high altitude, read this important information about adjusting canning times.)  

FREEZER JAM OPTION: Don't want to break out the canner? Simply allow the jars to completely cool on your countertop, then pop them into the freezer.

TO MAKE THE JAM SEEDLESS: Before step 1, place a mesh strainer (like this) over a large bowl. Spoon the mashed blackberries into the strainer and press them through the mesh with the back of a wooden spoon. The seeds will remain in the strainer, while the berry pulp will plop into the bowl. Proceed with making the jam, beginning with step 1.

* Be sure your thermometor is accurate! My first batch would not come up to temp. Finally, I realized the jam was thicker than it should be...and that my thermometor simply wasn't accurate. Grrr! TO CHECK THE ACCURACY OF YOUR THERMOMETER: Bring some water to a rolling boil and take it's temperature (without allowing the thermometer to touch the bottom or sides of the pan). Wear an oven mitt so you don't burn yourself. Water boils at 212 degrees F. (sea level).

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