5 of 6 berries records are published. The wall fills in as the season turns.
Fast, hot, short boils
Raspberry has a delicate aroma that survives about eight minutes of boiling and then simply is not there any more. This recipe keeps the set honest with added pectin and a short boil, then folds in a small amount of uncooked fruit at the end — enough to bring back the top note without putting raw fruit in the jar.
Blueberries read as tart, but that is tannin in the skin, not acid: the flesh sits at pH 3.8 to 4.2, high enough that a plain blueberry jam sets weakly and tastes flat. Lime juice and lime zest pull the pH down to 3.2 and give the fruit the backbone it lacks on its own.
Blackberries carry medium pectin and good acid, so they set easily — the problem is the seeds. Every blackberry has 20 to 40 of them, they are hard enough to crack a tooth, and because they are attached to the core they survive even a long cook. This recipe separates the fruit from the seed before the sugar goes in.
Redcurrants are the most reliable jelly fruit that grows in a temperate garden: pectin so abundant that a litre of juice gels with nothing added, and enough acid to set at a pH where no mould can grow. Make this once and you have a reference for what a proper set feels like.
Strawberries are the worst jam fruit in the book: low pectin, high water, and pigments that collapse into brown sludge if you boil them hard. Everything about a good strawberry preserve is about removing water before the fruit breaks down, which is why this recipe macerates overnight and boils in two short hits.
Listed newest first by publication date. Seedless Raspberry Jam with a Fresh, Uncooked Edge