4 of 6 stone fruit records are published. The wall fills in as the season turns.
Skin carries the pectin
Plums have plenty of pectin but it hides in the skin, and plum skin is also where the tartness lives. The result is that plum jam made from peeled fruit is both sweet and loose, while the same fruit cooked skin-on sets firmly and tastes of something. Keep the skins, keep the acid, and let cardamom bridge the two.
A white peach has roughly half the acid of a yellow one and a fragrance that lives entirely in the skin — which is also the part you have to remove, because peach skin turns into a bitter, papery strip in the jar. The answer is a ten-second blanch: the skin slips off with the aroma still on the fruit.
Sour cherries carry almond aroma in their pits and pectin in their skins, and both are lost the moment you pit them. Leaving the pits in means a batch that perfumes the kitchen and sets without help — the only cost is 20 minutes of work warning everyone at the table.
The kernels inside apricot stones carry benzaldehyde, the same aromatic that makes bitter almond, and ten of them will perfume a whole batch for the cost of a minute with a hammer. Without them apricot jam is pleasant; with them it tastes like the apricots you remember from a holiday.
Listed newest first by publication date. Plum Jam with Cardamom and a Firm Set