Grapes in Jelly

A layered gelatin mould that depends entirely on patience: each stratum must be nearly firm before the next goes in, or the grapes drift and the layers blur.

• Gelatine quantityTwo tablespoons of granulated gelatine is a little over two envelopes (about 1/2 to 2/3 oz), enough to set a quart firmly so it will unmould and slice. Modern dessert jellies often use less; if you want a softer set, drop to about one and a half envelopes, but a soft mould will not stand up on a plate.
• "Dissolved gelatine"Soften the gelatine in about 1/4 cup cold water or cold grape juice for five minutes, then stir it into the hot juice until no grains remain. Count that cold liquid as part of the quart. The juice should be hot but not boiling; prolonged boiling weakens the set.
• SweeteningThe recipe calls for no sugar, which suggests the juice was expected to be sweet already, as home-pressed or bottled grape juice generally was. Unsweetened juice will want 1/3 to 1/2 cup sugar per quart, dissolved in the hot juice before the gelatine goes in, plus a squeeze of lemon to keep it from tasting flat.
• The grapes"Cut in half and seeded" points to slip-skin Concord or Catawba grapes, which have seeds and loose skins. Seedless table grapes need only halving; halve them lengthwise and lay them cut side down against the mould for a neater pattern.
• Layer timingChill each layer 20 to 30 minutes, until tacky and set at the surface but not fully firm; layers left to harden completely bond less well, and the mould can separate along the seams when turned out. Keep the reserved jelly at room temperature so it stays pourable; if it sets in the jug, warm it gently rather than reboiling.
• Total chillingExpect two to three hours of building for a four- or five-layer mould, then at least four hours, or overnight, before unmoulding.
• UnmouldingDip the mould in hot water for ten seconds, loosen the edge with a wet fingertip, and invert onto a chilled wet plate so the jelly can be slid into position. Rinsing the mould with cold water before the first layer also helps.
• YieldA quart of jelly fills a 1 1/2-quart mould with the fruit and serves six to eight. Sweeten the whipped cream lightly; the grape jelly is assertive.