Mint Jelly

A contributor's shorthand rather than a full recipe: it assumes you already know how to make jelly from underripe grapes and simply tells you where the mint goes. A few blanks are worth filling in.

• The hinge: infuse briefly, then strainMint's flavor is in volatile oils that go grassy and bitter with long contact with boiling sugar syrup. Bruise the leaves, steep them in the finished hot jelly for a few minutes only, then strain into the jars as directed. Leaving a whole leaf sealed in the glass, as the first option suggests, mostly gives you a decorative leaf and little flavor.
• "Green grape jelly"This most likely means jelly made from hard, underripe grapes rather than from a green-skinned variety. Underripe fruit is high in both pectin and acid, so the base sets without commercial pectin and gives a pale, tart, neutral jelly that carries mint well; fully ripe grapes are lower in pectin and acid and set less readily.
• Judging the setWith no added pectin you are cooking to concentration: the jelly is done at about 220F at sea level, or roughly 8 degrees above the boiling point of water where you are. The sheeting test off a cold metal spoon works if you have no thermometer.
• "Glasses"Period jelly glasses held 6 to 8 ounces and were sealed with a disc of melted paraffin. Skip the paraffin; it cools with pinholes and shrinkage gaps that mold colonizes. Use standard half-pint jars with two-piece lids and process in a boiling water bath for 10 minutes.
• Straining"Strain in glasses" most likely means straining as you fill, through a jelly bag or several layers of damp cheesecloth, catching both mint debris and any scum. Do not squeeze the bag or the jelly clouds.
• The coloringGreen food coloring is what makes this jelly resemble the commercial product; the fruit itself gives a pale, straw-colored jelly. A drop or two of liquid green, stirred in off the heat, is plenty, and it is entirely optional.
• YieldNot stated. Reckon on about four half-pints from 4 lb of underripe grapes, which is a normal batch for a single kettle. Jelly does not scale up well; doubling means longer boiling and a duller flavor.