Tuscan Tomato Herb Jam Recipe and Canning

Wash the jars, lids, and bands in warm, soapy water and rinse well. Place the jars right side up in a boiling‑water canner fitted with a canning rack . Do not boil lids. Add warm water until it covers the jars by about 1 inch. Bring the water to a boil and boil the jars for 10 minutes if you are below 1,000 feet elevation; add 1 minute of boiling time for every additional 1,000 feet. Reduce the heat and keep the jars hot until you’re ready to fill them.

Wash 6 pounds of tomatoes thoroughly under cool running water, removing any dirt or debris. San Marzano (pictured), Roma, or other small plum varieties work especially well for this recipe.

Bring a large pot of water to a boil. Score the bottom of each tomato with a small “X,” cutting just through the skin but not into the flesh. Fill a large stainless‑steel bowl with a couple of cups of ice and a couple of cups of cold water to create an ice‑water bath.

Carefully lower the tomatoes into the boiling water and blanch for 30–60 seconds. The skins will begin to loosen and split at the scored “X.” Do not overcook — you’re just loosening the skins, not cooking the flesh.

Then, using a slotted spoon, remove the tomatoes from the boiling water and immediately transfer them to the ice‑water bath. This stops the cooking process and helps the skins loosen fully, making them easy to peel.

Remove the skins from all of the tomatoes. Trim away any fibrous parts that could affect the texture and cut out the tough core at the stem end. Discard or mulch these pieces and set the prepared tomatoes aside.

Place all of the diced tomatoes into a non‑reactive stainless‑steel or enameled pot over medium heat. Cook, stirring occasionally, until the volume is reduced by about half, which will take roughly 45–60 minutes depending on the juiciness of the tomatoes.

Increase the heat to medium high Add 6 tablespoons of powdered pectin to the reduced tomatoes.

Immediately stir in 1/4 cup of dry white wine, 1/4 teaspoon of black pepper, 1 teaspoon each of lemon zest, salt, dried summer savory, and ground rosemary. Add 2 tablespoons of balsamic vinegar (at least 5% acidity) and 2 tablespoons of bottled lemon juice. Use bottled lemon juice instead of fresh, since its consistent acidity ensures the tomato jam is safe for water‑bath canning. Fresh lemon juice varies in pH depending on the type and age of the lemons, making it unreliable for safe preservation. Stir until everything is well combined and return the mixture to a full boil, stirring constantly.

Add 1 1/2 cups of granulated sugar, stirring to dissolve. Bring mixture to a rolling boil that cannot be stirred down. Boil hard for 1 minute, stirring constantly. Remove from heat. Skim foam if necessary.

Ladle the hot jam into hot jars, leaving 1/4‑inch of headspace—the space between the jam and the underside of the lid. This gap allows the contents to expand during processing and ensures a proper vacuum seal as the jars cool.

Remove any large air pockets or bubbles with a non-reactive air bubble tool to release trapped air and ensure proper headspace for a safe seal. Wipe the jar rims with a clean, damp towel to remove any residue that could interfere with sealing.

Center the lids on the jars, making sure each one sits evenly to ensure a proper seal.

Place the bands on the jars, tightening them to fingertip tightness—snug but not overly tight.

Carefully lower the jars into the boiling water, keeping them upright. When using a jar lifter, make sure it is securely positioned below the jar neck (below the screw band of the lid). Tilting the jar could cause food to spill into the lid's sealing area. Make sure the water covers the jars by 1–2 inches. Place the lid on the canner. Begin timing once the water returns to a full boil. Process 8-ounce half-pint jars for 15 minutes at elevations from sea level to 1,000 feet. For 1,001–3,000 feet, process for 20 minutes; for 3,001 to 6,000 feet, 25 minutes; for 6,001 to 8,000 feet, 30 minutes; and for 8,001 to 10,000 feet, 35 minutes.

When the processing time is complete, turn off the heat, move the canner off the burner if possible, and carefully remove the lid. Let the jars rest in the hot water for 5 minutes before lifting them out. Place the jars upright on a towel‑lined countertop and leave them undisturbed for 12 to 24 hours. Jars may take several hours to seal, though many seal within the first 30 minutes or even during processing. After 12 hours, check the seals and clean the jars. Label with contents and date—store sealed jars for up to one year. Refrigerate any jars that did not seal.

Enjoy!

For more delicious canning recipes, here are a few of our favorites:

• Huckleberry Jam Recipe and Canning.
• Apple Cinnamon Jelly Recipe and Canning
• Blackberry Jam Recipe and Canning
• Blueberry Jam Recipe and Canning
• Fig Jam Recipe and Canning
• Pomegranate Jelly Recipe & Canning
• Pepper Jelly Recipe & Canning
• Peach Jam Recipe and Canning
• Mint Jelly Recipe & Canning
• Cheddar Herb Biscuits (shown in the photos)