Grapefruit Marmalade

Prepare Jars: Inspect two 5-ounce jars for any cracks or rust. Discard any defective ones. Immerse the jars in simmering water to sterilize. Wash new, unused lids and rings in warm, soapy water and set aside. (15 minutes)

Prepare Grapefruit Zest: Thoroughly wash and dry the grapefruits. Using a zester, carefully remove the zest from two grapefruits, creating delicate ribbons. Set the zest aside. (10 minutes)

Prepare Grapefruit Peel: With a sharp paring knife, carefully peel thin strips of zest from the remaining two grapefruits, avoiding the bitter white pith. (10 minutes)

Prepare Grapefruit Segments: Peel off all remaining outer white pith from all grapefruits and discard. Slice the grapefruits into wheels and remove any seeds. (15 minutes)

Combine and Cook: Place the grapefruit wheels and zest strips into a non-reactive saucepan. Add the sugar and stir well to ensure the fruit is fully coated. Heat over medium-high heat, stirring constantly until the mixture begins to bubble. Smash the heated fruit with a spoon or potato masher until it begins to liquefy. Reduce the heat to low and maintain a steady simmer, stirring frequently. (20 minutes)

Remove Froth: As the marmalade cooks, remove and discard any persistent white froth that appears on the surface. This ensures a clear, vibrant final product. (5 minutes)

Test for Setting Point: Continue to cook for about 10 minutes, or until the marmalade begins to thicken and coat the back of a spoon. To test for the setting point, place a small spoonful of marmalade on a chilled plate and place it in the freezer for 3 minutes. (13 minutes)

Incorporate Zest Ribbons: Add the reserved grapefruit zest ribbons to the marmalade and cook for an additional 5 minutes to infuse their aromatic oils. (8 minutes)

Final Set Test: Remove the marmalade from the heat when the freezer sample has reached your desired consistency - it should wrinkle slightly when pushed with a finger. (3 minutes)

Fill Jars: Carefully pack the hot grapefruit marmalade into the hot, sterilized jars, leaving about 1/4 inch of headspace at the top. Run a clean knife or thin spatula around the inside of the jars to release any trapped air bubbles. Wipe the rims clean with a moist paper towel to remove any residue. (10 minutes)

Seal Jars: Top each jar with a lid and screw the rings on tightly, but not excessively so. (2 minutes)

Process in Boiling Water Bath: Place a rack in the bottom of a large stockpot and fill it halfway with water. Bring the water to a boil. Using a jar lifter, carefully lower the filled jars into the boiling water, ensuring they are at least 2 inches apart. Add more boiling water, if needed, to cover the jars by at least 1 inch. Bring the water back to a rolling boil, cover the pot, and process for 10 minutes. (25 minutes)

Cool and Check Seals: Carefully remove the jars from the stockpot and let them rest, several inches apart, on a towel-lined surface for 24 hours. Avoid disturbing the jars during this time. After 24 hours, press the center of each lid with a finger to ensure it does not move up or down. This indicates a proper seal. (24 hours)

Store: Remove the rings for storage and store the sealed jars in a cool, dark place. Properly processed and sealed marmalade can be stored for up to a year.