Black Raspberry Jam

Black raspberry jam is a delicious way to preserve this short-season summer fruit, and it comes together with just a few ingredients (no boxed pectin needed).

Black raspberries, or blackcaps, aren’t the same fruit as the red raspberries at the store. They’re smaller and darker, with more seeds and a stronger flavor that holds up to a hard boil.

You’ll rarely see them for sale. They bruise if you look at them wrong, so they don’t travel well, and most people either grow them or know a patch that comes up wild. Here in Vermont, the berries trickle in over a few weeks in midsummer.

They’re easy to mix up with blackberries. Pick one and look at the end. A black raspberry pulls free of its core and comes away hollow, like a red raspberry, while a blackberry keeps its white core inside. If what you’ve got are blackberries, make my old-fashioned blackberry jam instead.

Black raspberries have plenty of natural pectin, so this jam sets without any added boxed stuff. Cook it to the gel stage, and it firms up in the jars over the next day or two. It’s the same process as making jam without added pectin.

If you’d rather skip the seeds, my black raspberry jelly strains them all out. I also have black raspberry pie filling for a bigger harvest, plus a long list of raspberry canning recipes to put up the rest. Beyond canning, there are plenty of black raspberry recipes for the berries that never make it to the pot.

Ingredients for Black Raspberry Jam

Wild or garden berries both work here, and so do frozen ones. If you come up a little short, some red raspberries or wineberries can fill out the batch, and lime juice can be used in place of lemon.

• Black raspberries: Fresh or frozen, wild or cultivated. Sort out stems, leaves, and any soft or moldy berries as you rinse. A few that are a shade underripe help the set, since underripe fruit has more pectin. Frozen berries can go in straight from the freezer. Freezing breaks down some pectin, but the skins and seeds hold plenty, so the jam still sets.
• Sugar: Plain granulated sugar. It sweetens and helps the jam set, but it isn’t what keeps it safe, so you can adjust it. There’s half as much sugar as fruit here, which keeps the berry flavor up front.
• Lemon juice: There’s enough natural acid in black raspberries for water bath canning without help. The lemon brightens the flavor and adds a little pectin. Bottled lemon juice or fresh both work, and lime juice is fine in a pinch.

Pick a wide, heavy-bottomed pot with room to spare, because this jam foams up high when it boils. Put a small saucer in the freezer for the gel test, and get the canner heating before you start. A small batch moves fast at the end.

How to Make Black Raspberry Jam

It’s a quick jam, about 15 to 20 minutes on the stove. Everything goes into the pot together, and there’s no overnight soak. Stoves vary, so go by the thermometer and the frozen plate test instead of the clock.

The ratio is 4 cups black raspberries to 2 cups sugar and 2 tablespoons lemon juice. If you’re working by weight, that’s about 1 1/2 pounds of berries to 14 ounces of sugar.

Stay close to the stove. Once it starts to thicken, a small batch of jam can go from runny to scorched in a minute.

Prep the Berries

Rinse the berries in a colander and pick out stems, leaves, and anything soft or moldy.

Wild berries sometimes come with passengers. Let them sit for a few minutes in a bowl of water with a splash of vinegar to chase out any bugs, then rinse and drain.

Cook the Jam

Put the berries, sugar, and lemon juice in a wide, heavy pot over medium heat. Mash the berries with a potato masher as they warm, until they’ve given up their juice and the sugar has melted into it.

Once the pot is loose and syrupy, raise the heat and let it come up to a hard boil, the kind that doesn’t stop when you stir. Keep stirring and scraping the bottom while it boils.

One reader got tired of mashing and ran the berries through a blender first. That works fine too, but it’s not really necessary. The berries fall apart pretty quickly while cooking.

Test the Gel Stage

Give it 8 to 10 minutes at a hard boil, then start checking. On an instant-read thermometer, the jam is ready at 220 degrees F at sea level. Subtract roughly a degree for every 500 feet you are above sea level, so at 1,500 feet you’re looking for 217.

For the plate test, drop a little jam on the frozen saucer, give it a minute, and push it with a fingertip. If the surface wrinkles, it’s ready.

Trust the thermometer over how the jam looks. One reader stopped at 215 degrees because it looked right, and the batch never set. Don’t stop early.

Take the jam off the burner as soon as it gels. Jam without added pectin keeps thickening the longer it cooks, and a few extra minutes turns it stiff.

Making Seedless Black Raspberry Jam

Black raspberries are seedy, and some people would rather go without. I don’t mind the seeds, but if you do, simmer the berries briefly until they break down, then press them through a fine mesh strainer. My seedless raspberry jam covers the straining, and black raspberries go through it the same way.

For a smooth, clear spread, strain the juice through a jelly bag instead and make black raspberry jelly. I’ve made it with no added pectin, and it sets up well.

Use fresh berries for jelly, though. Freezing breaks down enough pectin that strained juice from frozen berries may not set.

Canning Black Raspberry Jam

Have your water bath canner hot and the jars warm before the jam is done. Fill the jars while the jam is still hot, because jam that’s cooled off won’t heat through properly in the canner.

Ladle the jam into half-pint jars through a canning funnel, leaving 1/4 inch headspace. Wipe each rim clean, and put the lids and bands on fingertip tight.

Process half pints for 10 minutes in a boiling water bath, adjusting for altitude with the chart below. Then shut off the burner and let the jars sit in the canner another 5 minutes, which keeps the jam from siphoning out under the lids. If you’re new to it, my water bath canning guide walks through the basics.

Lift the jars onto a towel and leave them alone for 12 to 24 hours before you check the seals.

Setting Notes

Black raspberry jam keeps setting after it goes in the jars. It looks loose when you fill them, and that’s normal. Give it 24 to 48 hours before you decide anything.

It should set up nicely, with enough body to stay put on toast. If it’s still runny after two days, it probably didn’t quite reach the gel stage.

You can open the jars, cook the jam back up to temperature with a little more lemon juice, and can it again with new lids. My guide to troubleshooting jelly set walks through it. Or label it syrup and pour it over pancakes.

Ways to Use Black Raspberry Jam

It’s a toast jam first, and it’s good on a buttered English muffin. Stir it into plain yogurt or oatmeal, or warm a spoonful and pour it over vanilla ice cream.

For baking, use it in place of red raspberry jam in Danish raspberry bars, spread it between cake layers, or spoon it into thumbprint cookies.

If you need more ideas, there’s a long list of recipes that use jam.

Storage and Shelf Life

Once the jars are cool, press the center of each lid. A sealed lid is firm and doesn’t flex. Take the rings off before the jars go on the shelf, so a seal that lets go later is easy to spot.

If a jar doesn’t seal, put it in the refrigerator and eat it within a week or two. You can also reprocess it with a fresh lid if you catch it within 24 hours.

Sealed jars stay good for 12 to 18 months on a cool, dark shelf. Once a jar is open, keep it in the fridge and use it within 1 to 2 weeks.

You don’t have to can it. Unprocessed jam holds for several weeks refrigerated, or up to 6 months in the freezer in straight-sided, freezer-safe jars with 1 inch headspace.

More Ways to Preserve Black Raspberries

Seedless black raspberry jelly is the smooth option, and black raspberry pie filling is the one for a big harvest. For more berry ideas, there’s freeze-drying raspberries as well.

If you’re still learning where they grow, there’s a guide to foraging wild black raspberries, and one on taming wild black raspberries into a patch you can pick. The rest are in my fruit canning recipes.

Black Raspberry Jam FAQs

Pectin, frozen berries, and how many berries it takes are what readers ask about most.

Raspberry Canning Recipes

More ways to put up raspberries, black and red.

Black Raspberry Jelly (Seedless)

Classic Raspberry Jam (without Added Pectin)

Canning Raspberry Pie Filling

Have the canner out already? Here are more jam canning recipes and the rest of my water bath canning recipes.

Jam Canning Recipes

More jams that set without a box of pectin.

Pear Jam

Caramelized Onion Jam

Blueberry Jam (without Added Pectin)

Looking for something a little different?