Christmas Jam

Ingredients

Christmas Jam

• 900g (6 cups (about 2 lb)) Strawberries, hulled and halved (fresh or frozen)
• 340g (3 cups (one 12 oz bag)) Cranberries, fresh or frozen
• 800g (4 cups) Granulated sugar
• 60ml (1/4 cup) Bottled lemon juice
• 2g (1 tsp) Ground cinnamon
• 0.5g (1/4 tsp) Ground cloves
• 0.5g (1/4 tsp) Freshly grated nutmeg

Equipment

Method

Prep and Macerate the Fruit

Cranberries are loaded with natural pectin, which is why this jam sets without a box of the commercial stuff. The strawberries bring sweetness and that classic jammy perfume. A short macerate pulls juice out of the fruit before the heat goes on, so nothing scorches.

1. Weigh the fruit. Hull and halve the strawberries, then weigh them. You want 900g after hulling, not before. Pick over the cranberries and toss any soft ones. Frozen fruit works fine for both, no need to thaw.
2. Macerate. Combine the strawberries, cranberries, sugar, and bottled lemon juice in your pot. Stir, then let it sit 30 minutes. The sugar will pull a surprising amount of juice out of the berries. Use bottled lemon juice here, not fresh. Its acidity is standardized, and consistent acidity is what keeps a canned jam safe.

Tip: Short on time tonight? Macerate the fruit in the fridge overnight and cook the jam tomorrow.

Cook to the Gel Point

No boxed pectin means you cook the jam until the cranberries' own pectin takes over. That happens at the gel point: 220°F (104°C) at sea level. The spices go in near the end so they stay bright instead of stewed.

1. Bring to a boil and mash. Set the pot over medium-high heat and bring it to a boil, stirring often. Once the cranberries start popping, mash the fruit with a potato masher. Leave some texture if you like a chunkier jam. Smooth it out more if you're going for gift-jar pretty.
2. Boil to the gel point. Keep the jam at a strong boil, stirring more and more often as it thickens so the bottom doesn't catch. It'll foam early, then the bubbles get glossy and slow. You're looking for 220°F (104°C) on the thermometer, usually 25-35 minutes. At altitude, the target drops about 2°F for every 1,000 feet above sea level, so above 3,000 feet aim for 214°F (101°C).
3. Add the spices. In the last 5 minutes of cooking, stir in the cinnamon, cloves, and nutmeg. That's enough time for them to bloom in the hot jam without going muddy.
4. Confirm the set. Pull the pot off the heat. Spoon a little jam onto your freezer-cold plate, wait 60 seconds, then push it with a fingertip. If the surface wrinkles, you're set. If it runs like syrup, boil 3-5 minutes more and test again. Skim any foam off the surface with a spoon.

Jar It: Two Methods

This is a high-acid jam, cooked fruit plus bottled lemon juice, which makes it safe for boiling water bath canning. No pressure canner needed. If you'd rather skip canning altogether, the refrigerator version needs nothing but clean jars.

Oven: 104°C / 220°F. Internal temperature when done: 104°C / 220°F.

Water-Bath Canned (Shelf-Stable) (recommended)

The gift-giving method. Sealed jars keep in the pantry for 12-18 months.

Equipment: Water bath canner or deep stockpot with rack,6 half-pint jars with new flat lids

1. Get the jars hot. Before you cook the jam, fill the canner with water, load the clean jars, and bring it to a simmer. The jars need to be hot when you fill them so they don't crack. Simmer the new flat lids in a small pan of water off the boil, or just wash them well per the manufacturer's directions.
2. Fill with 1/4 inch headspace. Working one jar at a time, ladle hot jam through the canning funnel into a hot jar, leaving 1/4 inch (6mm) of headspace below the rim. That gap is what lets the jar pull a proper vacuum. Run a clean chopstick around the inside to release air bubbles and top up if needed.
3. Wipe, lid, and band. Wipe each rim with a clean damp cloth. Even a smear of jam on the rim can block the seal. Center a flat lid, then screw the band down fingertip tight. Snug, not cranked.
4. Process 10 minutes. Lower the jars onto the rack so they're covered by at least 1 inch of water. Bring to a full rolling boil, then start your timer: 10 minutes at 0-1,000 feet. Above 1,000 feet, add time: 15 minutes for 1,001-6,000 feet, 20 minutes above 6,000 feet.
5. Rest, then lift out. Kill the heat, take the lid off the canner, and let the jars stand in the water 5 minutes. This settles the contents and cuts down on siphoning. Then lift the jars straight up with the jar lifter and set them on a towel. Don't tilt them and don't retighten the bands.
6. Cool and check the seals. Leave the jars undisturbed 12-24 hours. You'll hear the lids ping as they seal. Next day, press the center of each lid. A sealed lid is concave and doesn't flex. Any jar that didn't seal goes in the fridge, eat that one first. Remove the bands from sealed jars, wipe them down, label, and store in a cool dark pantry.

Refrigerator Version (No Canning)

Same jam, zero processing. Perfect if this is your first batch ever.

Equipment: 6 clean half-pint jars or containers with lids

1. Fill clean jars. Ladle the hot jam into clean jars, leaving 1/2 inch (12mm) of headspace. No sterilizing marathon needed, just jars fresh from a hot soapy wash or the dishwasher.
2. Cool, then lid. Let the jars sit on the counter until barely warm, about an hour, then put the lids on and refrigerate.
3. Store cold or freeze. Refrigerated jam keeps about 3 weeks. For longer storage, freeze straight-sided jars up to 6 months. Keep that 1/2 inch headspace or the expanding jam will crack the glass.

Note: Gel point, not oven temp: 220°F (104°C) at sea level is when this jam sets.

Storage

• Room temperature: Sealed water-bath jars: 12-18 months in a cool, dark pantry. Once opened, refrigerate and use within 3 weeks.
• Frozen: Refrigerator-version jam freezes up to 6 months in straight-sided jars with 1/2 inch headspace. Thaw in the fridge overnight.

Store sealed jars without the bands. If a lid ever loses its seal in storage, you'll spot it immediately.

Frequently Asked Questions

Is water-bath canning actually safe for this jam?

Yes. Botulism risk lives in low-acid foods. This jam is high-acid, fruit plus a measured dose of bottled lemon juice, and high-acid foods are exactly what boiling water bath canning was designed for. Follow the headspace, the processing time for your altitude, and the seal check, and you're solidly inside safe practice.

Why no boxed pectin?

Because the cranberries already carry more pectin than most commercial boxes deliver. Cook the fruit with sugar and acid to 220°F (104°C) and it sets on its own. You also skip the chalky texture boxed pectin can bring.

Can I cut the sugar?

Not by much. Sugar isn't just sweetness here, it's structure and preservation. Drop it more than about 10% and the set gets loose and the shelf life shortens. If you want a true low-sugar jam, that's a different recipe built for it, not this one with sugar removed.

My jam didn't set. What now?

First, wait. Jam keeps firming for 24-48 hours after canning. If it's still syrup after two days, open the jars, return the jam to the pot, boil it back to 220°F (104°C), and re-can in clean jars with new flat lids. Or just relabel it Christmas Syrup. It's outstanding on pancakes and nobody has ever complained.

Can I use frozen strawberries and cranberries?

Absolutely. Weigh them frozen, skip thawing, and expect a few extra minutes of cook time while the extra ice boils off. The set and flavor come out the same.

The jars sealed but there's a little jam residue in the water. Did I ruin them?

That's siphoning, a bit of jam escaping during processing. If the lid sealed and passes the press test the next day, the jar is fine. Wipe it clean and store it. Heavy siphoning usually means the jars went in overfilled or came out too fast, so keep that 5-minute rest in the canner.

Nutrition

Per serving (1 tablespoon (20g)): 35 calories, 9g carbohydrates, 0g protein, 0g fat, 0g fiber, 0mg sodium. Makes 96 servings.