Black raspberry jam is a delicious way to preserve this short-season summer fruit. This small-batch recipe uses just a few ingredients and sets without boxed pectin.
This recipe has been reviewed for safety and accuracy by a Master Food Preserver certified through the University of Cornell Cooperative Extension.
Black raspberries, often called blackcaps, are a different fruit from the red raspberries sold in most stores. They are smaller, darker, and seedier, with a concentrated flavor that stands up well to a hard boil.
Because they bruise easily they are rarely sold commercially; most people either grow them or find wild patches. In some regions they ripen over a few weeks in midsummer, which makes small-batch cooking and freezing a practical approach.
A quick way to tell black raspberries from blackberries is by the core: black raspberries pull free of their core and leave a hollow fruit, like red raspberries; blackberries keep their white core inside. If you have blackberries instead, use a blackberry jam method.
Black raspberries contain ample natural pectin, so this jam sets without added boxed pectin. Cook the fruit to the gel stage and the jam will firm up in the jars over the next day or two. The process is the same as other jams made without added pectin.
If you prefer a seedless spread, you can strain the cooked berries and make jelly instead. For larger harvests, turning berries into pie filling or freezing them for later use are both good options.
Notes from My Kitchen
The black raspberries in my orchard arrived on their own. Each summer the kids forage and snack as they pick; I follow with a jar collecting the leftovers they miss. On a good day this yields enough for a batch of jam. If the harvest comes in slowly, I refrigerate the berries for a few days or freeze them until I have enough for a pot.
Quick Look at the Recipe
- Recipe Name: Black Raspberry Jam
- Recipe Type: Jam (no added pectin)
- Canning Method: Water bath canning
- Prep Time: About 10 minutes
- Cook Time: About 15–20 minutes; go by temperature
- Canning Time: 10 minutes for half pints (adjust for altitude)
- Yield: About 3 half pints
- Jar Sizes: Half pints or quarter pints
- Headspace: 1/4 inch
- Ingredients Overview: Black raspberries, sugar, lemon juice
- Difficulty: Easy
Ingredients for Black Raspberry Jam
Wild or garden berries both work, and frozen berries can be used straight from the freezer. If you come up a little short, red raspberries or wineberries can pad the batch, and lime juice can substitute for lemon.
- Black raspberries: 4 cups whole (fresh or frozen). Sort out stems, leaves, and any soft or moldy fruit. A few underripe berries help the set because underripe fruit contains more pectin. Frozen berries can be used directly; while freezing breaks some pectin down, skins and seeds retain enough for jam.
- Sugar: 2 cups granulated sugar. Sugar enhances flavor and helps with texture; this recipe uses half as much sugar as fruit to keep the berry flavor bright. You can reduce sugar, but expect a longer boil and a softer set.
- Lemon juice: 2 tablespoons. Lemon brightens flavor and adds a bit of pectin. Bottled or fresh juice both work; lime is a fine substitute in a pinch.
Choose a wide, heavy-bottomed pot with room for foaming; jam can foam up when it boils. Place a small saucer in the freezer to use for the gel test, and have your canner heating before you start because a small batch finishes quickly.
Low Sugar Options
You can reduce the sugar and still safely water-bath can this jam because the fruit’s acidity provides preservation. Less sugar requires more cooking time to reach the gel stage, produces a looser set, and yields slightly less finished jam.
Honey or maple syrup can replace up to half the sugar, with organic cane juice as an option for the remainder; these alternatives scorch more easily, so stir constantly. Non-nutritive sweeteners are not recommended for canned jam because they do not set and are not tested for canning.
How to Make Black Raspberry Jam
This is a quick jam: plan about 15–20 minutes on the stove. Everything goes into the pot together—no overnight maceration. Because stove output varies, go by temperature and the frozen saucer test rather than the clock.
Ratio: 4 cups whole black raspberries to 2 cups sugar and 2 tablespoons lemon juice. By weight this is roughly 1 1/2 pounds berries to 14 ounces sugar.
Stay by the stove as the jam thickens; a small batch can go from perfect to scorched in a minute.
Prep the Berries
Rinse the berries in a colander and remove stems, leaves, and any soft or moldy fruit. If you picked wild berries, let them sit briefly in a bowl of water with a splash of vinegar to dislodge any small insects, then rinse and drain.
Cook the Jam
Combine berries, sugar, and lemon juice in a wide, heavy-bottomed pot over medium heat. Mash the fruit with a potato masher as it warms until it releases juice and the sugar dissolves.
Raise the heat and bring the mixture to a hard boil—the kind that doesn’t stop when stirred. Stir and scrape the pot bottom while it boils to prevent scorching. You can puree the berries first if you prefer a very smooth texture, but it isn’t necessary; the fruit breaks down quickly while cooking.
Test the Gel Stage
After 8–10 minutes at a hard boil, start testing. The jam reaches gel at about 220°F at sea level on an instant-read thermometer. Adjust downward roughly 1°F for every 500 feet elevation (for example, 217°F at 1,500 ft).
For the plate test, drop a little onto the frozen saucer, wait a minute, and push it with your fingertip—if the surface wrinkles, it’s ready. Trust the thermometer over visual cues; stopping short can result in jam that never sets.
Remove the pot from the heat as soon as the jam reaches the gel stage. Jam without added pectin continues to thicken with more cooking, and a few extra minutes can make it overly stiff.
Making Seedless Black Raspberry Jam
If you want a seed-free spread, simmer the berries until they break down and press them through a fine mesh strainer. For a clear, smooth jelly, strain the cooked juice through a jelly bag and cook the strained juice to the gel stage. Use fresh berries for jelly when possible; freezing breaks some pectin and strained juice from frozen berries may not set as reliably.
Canning Black Raspberry Jam
Have a water bath canner hot and jars warm before the jam is ready. Fill hot jars with hot jam, leaving 1/4 inch headspace. Wipe rims clean and apply lids and bands fingertip-tight. Process half pints in a boiling water bath for 10 minutes (adjust for altitude).
After processing, turn off the burner and let jars sit in the canner for an additional 5 minutes to prevent siphoning, then remove and cool undisturbed for 12–24 hours before checking seals.
Altitude Adjustments
Water boils cooler at higher elevations, so processing times increase. For half pints and quarter pints:
- 0 to 6,000 feet: 10 minutes
- Above 6,000 feet: 15 minutes
Setting Notes
Jams made without added pectin often look loose when filled but continue to set in the jars. Allow 24–48 hours before judging the final texture. If the jam remains runny after two days, it likely didn’t reach gel; you can reheat it, add a little more lemon, and re-can it, or use it as a syrup.
Ways to Use Black Raspberry Jam
This jam is excellent on toast or an English muffin, stirred into yogurt or oatmeal, or warmed and spooned over ice cream. It also works in baking—swap it for other raspberry jams in bars, thumbprint cookies, or layered cakes.
Storage and Shelf Life
A sealed lid will be firm and not flex when pressed. Remove bands before storing so any failed seal is obvious. Unsealed jars should be refrigerated and used within one to two weeks, or reprocessed within 24 hours. Sealed jars store well for 12–18 months on a cool, dark shelf. Refrigerate opened jars. If you prefer not to can, refrigerated jam keeps several weeks or up to six months frozen with 1 inch headspace in freezer-safe, straight-sided jars.
More Ways to Preserve Black Raspberries
Seedless jelly is a smooth alternative, and pie filling suits a large harvest. Freezing, drying, or turning berries into syrups and sauces are additional preservation options depending on your needs.
Yield Notes
Four cups of whole berries weigh about 1 1/2 pounds and mash down to roughly 3 cups, enough for about three half-pint jars. Scale by cups of whole berries. The recipe halves and doubles easily; a double batch yields about six half pints but requires a few extra minutes to reach gel. Avoid much larger batches, as large pots can heat unevenly and may not set properly.
Black Raspberry Jam FAQs
Common questions cover pectin, frozen berries, batch size, and troubleshooting.
No. Black raspberries have plenty of natural pectin and the lemon juice adds a little more. Cooking to the proper gel temperature—about 220°F at sea level—is what creates the set.
Common causes are stopping the cook before the jam reached gel temperature, using overly ripe fruit with less natural pectin, or scaling the batch too large. Allow 24–48 hours to finish setting. If it still won’t set, you can re-cook and re-can the jam.
Yes. Frozen berries can go from the freezer straight into the pot. Skins and seeds retain enough pectin for jam, though strained juice from frozen berries may not set reliably for jelly.
Plan on 4 cups whole berries (about 1 1/2 pounds) for roughly 3 half-pint jars.
Yes. A double batch makes about 6 half pints and takes a few more minutes to reach gel. Avoid much larger batches to ensure even heating and a reliable set.
