4 of 6 citrus records are published. The wall fills in as the season turns.
Peel and pips do the work
Bergamot is bitter enough to strip paint and perfumed enough to scent a room, which makes it the most unbalanced marmalade fruit there is. The fix is arithmetic rather than technique: cut the bergamot with a bland high-pectin fruit and let the aromatic peel speak at a lower concentration.
A kumquat is the only citrus you eat skin and all, so the preserve is judged on the texture of the rind, not the gel. Cook it too fast and you get leathery coins in a syrup so thick it will not pour; cook it in three short passes and you get translucent fruit suspended in a syrup that still runs off a spoon.
Yuzu skins carry roughly twice the aromatic oil of a lemon and its pips are a first-class pectin source, which makes it the best citrus for a crystal-clear jelly. The catch is that any pressure on the pulp clouds the batch permanently — clarity in jelly is decided while the juice is still dripping.
Seville oranges arrive for six weeks in January and carry enough pectin in their pith and pips that a marmalade needs no added gelling agent at all. The only thing that goes wrong is bitterness, and bitterness is a soaking problem, not a sugar problem.
Listed newest first by publication date. Bergamot Marmalade: Taming a Fruit That Is Mostly Aroma