Description
Looking to capture the sweet-tart magic of summer in a jar? Strawberry Rhubarb Jam is a classic preserve that blends the juicy sweetness of strawberries with the tangy zing of rhubarb, creating a vibrant, spreadable delight.
Ingredients
This Strawberry Rhubarb Jam uses simple, high-quality ingredients for a perfect balance of flavor and safety. Here’s what you need and why each one matters:
- Rhubarb (2 pounds, cut into ½-inch pieces): Provides tartness and structure, contributing to the jam’s unique flavor and texture.
- Strawberries (1 pound, not overripe, stems removed, cut into ¼-inch pieces): Adds sweet, juicy flavor and vibrant red color; avoid overripe berries to ensure proper set.
- Granulated Sugar (2½ cups): Sweetens the jam, helps it set, and acts as a preservative for canning.
- Bottled Lemon Juice (3 tablespoons): Ensures consistent 5% acidity for safe canning and enhances tartness; bottled is critical, as fresh lemons vary in acidity.
- Fine Salt (¼ teaspoon): Balances sweetness and enhances fruit flavors.
- Vanilla Bean Pod (1, seeds scraped out): Adds warm, aromatic depth for a gourmet touch.
Substitutions and Variations
- Rhubarb: Use frozen rhubarb (thawed and drained) if fresh isn’t available; adjust cooking time if wetter.
- Strawberries: Swap for frozen strawberries (thawed, not overripe); avoid other berries, as they alter acidity and safety for canning.
- Sugar: Reduce to 2 cups for a tarter jam, but don’t go lower to ensure proper set and preservation. Do not use sugar substitutes unless approved for canning (e.g., specific low-sugar pectin recipes).
- Lemon Juice: Do not substitute with fresh lemon juice for canning safety; vinegar (5% acidity) is an alternative but alters flavor.
- Salt: Omit if preferred, but it enhances flavor subtly.
- Vanilla Bean: Replace with 1 teaspoon pure vanilla extract (add after cooking to preserve flavor) or omit for a simpler jam.
- Add-Ins: For non-canned versions, try ½ teaspoon cinnamon or a pinch of ginger for warmth (avoid for canning unless tested for safety).
Pro Tip: Weigh fruit after trimming for accuracy (2 pounds rhubarb = ~6 cups chopped; 1 pound strawberries = ~2½ cups chopped). Use bottled lemon juice to ensure safe pH for water-bath canning.
Essential Equipment
- Water Bath Canning Pot: For processing jars to ensure shelf stability.
- Half-Pint Jars (6-8): Standard size for jam; ensure no cracks or chips.
- Jar Lifter: Safely moves hot jars in and out of boiling water.
- Lids and Bands: Use new lids for each batch to ensure a proper seal.
- Large Heavy-Bottomed Pot (e.g., 5.5-quart Dutch oven): For cooking jam evenly without burning.
- Small Plate: For testing jam set in the freezer.
- Thermometer (optional): To check jam temperature (~212°F for set).
- Kitchen Towel: For cooling jars and preventing countertop damage.
Pro Tip: Sterilize jars by simmering in the canner (not boiling) to keep them hot and ready; reuse bands but always use new lids for safety.
Instructions
- Macerate the Fruit:
- In a large glass bowl, combine 2 pounds chopped rhubarb, 1 pound chopped strawberries, and 2½ cups granulated sugar. Stir thoroughly to coat.
- Cover with plastic wrap and refrigerate for 12-24 hours to let the fruit release its juices.
- Tip: Stir once during maceration to ensure sugar dissolves; longer maceration (up to 24 hours) deepens flavor.
- Prepare for Canning:
- Remove fruit mixture from the refrigerator and stir in the seeds from 1 scraped vanilla bean pod.
- Wash 6-8 half-pint jars, lids, and bands in hot, soapy water; rinse well.
- Place jars in a water bath canner with the wire rack, cover with water, and bring to a simmer (180°F) to keep hot. Place lids in a small saucepan of warm (not boiling) water to soften seals.
- Place a small plate in the freezer for testing the jam’s set later.
- Tip: Keep jars hot to prevent cracking when filled with hot jam; don’t boil lids, as it can damage seals.
- Cook the Jam:
- Transfer the fruit mixture (with juices) to a large heavy-bottomed pot (e.g., 5.5-quart Dutch oven). Add 3 tablespoons bottled lemon juice and ¼ teaspoon fine salt.
- Bring to a boil over medium-high heat, stirring occasionally to prevent sticking.
- Once boiling, the mixture will foam. Reduce heat slightly to medium and stir every few minutes as it simmers rapidly, evaporating liquid and thickening (10-15 minutes).
- Tip: Skim heavy foam if desired for clearer jam, but some foam is normal; watch heat to avoid scorching.
- Test for Set (22-25 Minutes):
- As the jam thickens (around 22-25 minutes), stir frequently, scraping sides to prevent burning. The fruit will break down, and the mixture will become cohesive.
- Check temperature (optional): Aim for ~212°F for a thick set.
- Test set: Spoon a small amount of jam onto the chilled plate, tilt vertically, and observe the flow. It should descend slowly, not run quickly. Alternatively, let it sit on the plate for 30 seconds, then push with a finger or spoon; it should crease and not flood back together.
- If not set, cook 2-5 minutes more and retest. Cooking time varies based on fruit moisture (wetter fruit takes longer).
- Tip: Jam will thicken further as it cools; avoid overcooking to prevent a rubbery texture.
- Fill the Jars:
- Remove hot jars from the canner using a jar lifter and place on a kitchen towel.
- Ladle hot jam into jars, leaving ¼-inch headspace. Use a non-metallic spatula or bubble remover to release air bubbles.
- Wipe jar rims with a clean, damp cloth to ensure a good seal.
- Place lids on jars and screw on bands until fingertip-tight (not overly tight).
- Tip: Work quickly to keep jam and jars hot; measure headspace with a ruler or canning tool for accuracy.
- Process the Jars:
- Return filled jars to the canner, ensuring they’re covered by at least 1 inch of water.
- Cover the canner, bring to a rolling boil, and process for 10 minutes (adjust for altitude: add 1 minute per 1,000 feet above sea level).
- Turn off heat and let jars sit in the canner for 5 minutes to stabilize.
- Tip: Start timing when water reaches a full boil; ensure jars remain upright during processing.
- Cool and Store:
- Remove jars using a jar lifter and place on a kitchen towel on the counter, spacing them apart to cool.
- Let cool undisturbed for 12-24 hours. Check seals: Lids should be concave and not flex when pressed.
- Store sealed jars in a cool, dark place for up to 1 year. Refrigerate unsealed jars and use within 3 weeks.
- Tip: Label jars with the date and contents; listen for the “ping” as lids seal during cooling.
Cooking Tips:
- Prevent Burning: Stir frequently, especially as jam thickens, and use a heavy-bottomed pot for even heat.
- Test Early: Start checking the set at 20 minutes to avoid overcooking, as fruit moisture varies.
- Altitude Adjustments: Check your altitude and adjust processing time to ensure safe canning (e.g., 15 minutes at 5,000 feet).