Grapefruit Pulp Gelato

Sift the grapefruit seeds through a fine-mesh sieve

Place the extracted juice in a medium saucepan, along with the sugar

Simmer over low heat, stirring occasionally with a wooden spoon, for about 30 minutes, or until slightly thickened (test by lifting some of the gelato off the spoon; it should form two distinct streams); otherwise, place a small amount of the gelato on a flat plate and tilt the plate; the gelato should not run

Let it set for 4 hours.