Making Blackberry Jam

  • Difficulty Rating: Beginner
Making Blackberry Jam

Speaking from experience, when you've never done it, the idea of making jam is intimidating.

It must take a long time. There must be a lot of rules you have to follow so you don't make anyone who eats the jam sick. The process must be tedious. And speaking from experience, once you jump in and make your first batch of jam, when you're finished you wonder why you waited so long to discover how inaccurate your beliefs were about making jam.

I got started making jam a few years ago when we had a very successful year with our strawberry beds. Confident that it wouldn't affect his nightly consumption of strawberry shortcake, my husband suggested making jam. I knew it required pectin so I went to the store, found the boxes of pectin, and brought one home.

I used powdered pectin that day and continued to do so until I had a batch that didn't set up. The next morning I found myself with jars of strawberry syrup. Researching the internet for remedies led me to Liquid Certo. I've since switched to using it exclusively. Many people have great success with powdered pectin. Others prefer to keep things as natural as possible by extracting the pectin that is found naturally in other fruits such as apples and using it to thicken their jam. It's really a matter of personal preference. There is plenty of information about the process, in addition to recipes, available on the internet and in books. So far I have been perfectly pleased just using the instructions that come inside each box of pectin.

My mother-in-law grows thornless blackberry bushes and shares her harvest with us every year. I have to digress from jam making here and share that thornless blackberry bushes are wonderful. They obviously make picking blackberries much less painful but they also produce extremely large berries. I don't feel like there's any sacrifice in the quality of flavor over wild blackberries so I think thornless blackberry bushes are all around winners!

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Before you start making the jam, you'll want to sterilize your jars, lids, and utensils. Some people just wash their jars in hot soapy water and leave them in the water until they're ready to fill them. I like to take out as much risk as possible when it comes to processing my own foods so I sterilize my jars. An easy way to do this is to run them through a cycle in the dishwasher. If you don't have a dishwasher you have 2 more options. The traditional way to sterilize jars is to boil them in a large pot of water. I save time (and stove-top space) by sterilizing my jars in the microwave. I fill each jar at least 1/2 way with water, and run them through the microwave until the water boils for at least 1 minute. After that, they're out of the way keeping warm inside the microwave until I need them.

The lids, bands, and utensils also need to be sterilized but, because they are metal, should be sterilized in a saucepan of boiling water. This takes very little time to bring to a boil and can easily be set out of the way until needed.

The final preparation before starting to make the actual jam is to get a pot large enough to hold your jars (without touching one another), fill it about 1/2 way with water, and put on the stove on high heat to start the boiling process. I use the pot from my pressure canner to do this.

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After washing the berries, I run them through my blender. This step can be skipped if you don't mind seeds in your jam. I do, so I blend!

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The blended berries get poured into the strainer set over a large bowl or measuring cup and are pushed through the holes with a spoon. This may sound like a tedious process but it's not. Just stir, stir, stir. You'll repeat this process until you have collected 4 cups of pulp and juice. Alternatively, you can use a food mill to complete this step.

After pouring the 4 cups of pulp and juice in a large stock pot, you'll add 7 cups of sugar.

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Cooking the juice/pulp and sugar mixture over high heat, you'll bring it to a full rolling boil (one which you can't stir down) and continue stirring and boiling for 1 minute.

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Add the pouch of pectin, bring to a boil again, and boil exactly 1 minute.

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After turning off the heat, skim the foam off the surface of the jam. You do not want to skip this step. It cannot be stirred back into the jam later and it ruins the consistency of your jam. The longer it sits on the surface of the jam, the more it sets (becoming one with the jam) and the harder it is to remove it. You can add 1/2 tsp. of margarine or butter when you add the sugar which is supposed to help reduce the foaming.

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Dump the hot water out of the jars and fill them with the jam. I highly recommend using tools designed for canning. You can purchase sets of canning tools for under $15 and, in addition to making the canning process go much smoother, they make it safer. The set I bought included this funnel which makes filling the jars less messy and a jar lifter for safely removing the processed jars from the boiling water.

Prior to putting the jars in the water, put lids on them. First, wipe any excess jam off the rim. If you don't do this, anything that's trapped between the rubber seal of the lid and the lip of the jar will prevent the jar from sealing properly. You'll either end up doing it over again if you're lucky enough to discover it before you put the jars in your cabinet or you'll be throwing away your beloved jam months down the road. The lid is held down with a screw-on band.

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I use my canner to process my jams because it's huge and it has a removable canning rack in the bottom. See the metal plate with all the holes in it? The rack creates a buffer that prevents your jars from being rattled around on the bottom of the pot which can result in broken jars.

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The final step is to make sure the jars are covered with an inch to two inches of water. When the water reaches a boil (it's not fully boiling in this photo!) start your timer and continue boiling for 10 minutes.

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Using the jar lifter, remove the processed jars from the pot of water and set them on a towel.

The process for making jams using other fruits and berries is the same, although the measurements and, obviously the ingredients, are different. The insert in the Certo box includes recipes for quite a few varieties, as well as cooked jellies (these have all the pulp strained out of the juice) and freezer jams and jellies.

So now you see jam making really is very easy and doesn't take very long. The difference in taste over mass-produced jams is remarkable and, in my opinion, worth investing the time in making.