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Strawberry jam
Bruise very fine some scarlet strawberries, gathered when quite ripe, and put to them a little juice of red currants. Beat and sift their weight in sugar, strew it over them, and put them into a preserving pan. Set them over a clear slow fire, skim them, then boil them twenty minutes, and put them into glasses.
A three-line jam of the old school: equal weights of fruit and sugar, a splash of currant juice for set, and a short hard boil. Everything hinges on the sugar being weighed against the crushed fruit rather than measured by volume.
- Weigh, do not measure"Their weight in sugar" means the crushed berries go on the scale and an equal weight of sugar follows — roughly 2 lb sugar to 2 lb hulled fruit. Volume cups will not give you the same ratio and the jam will not keep as written.
- Beat and sift their weight in sugarSugar came as a hard cone that had to be broken up and sieved. Modern granulated sugar needs neither; use it straight from the bag, or preserving sugar if you want less scum.
- Scarlet strawberriesThis means the small, deeply coloured Fragaria virginiana types — the "Scarlets" of the old nurseries — grown before the big modern hybrids. Any ripe, well-flavoured strawberry works, but choose small fruit and avoid the pale, watery supermarket sort, which has less flavour and acidity.
- Why the currant juiceStrawberries are low in pectin and acid. A little red currant juice — the recipe does not quantify it; a few tablespoons per pound of fruit is a reasonable reading — supplies both and helps the jam set. Redcurrant jelly melted into the pan, or the juice of a lemon, does much the same job.
- Preserving panA wide, shallow, heavy nonreactive pan — the width matters more than the depth, because evaporation is what thickens the jam. A stockpot will take far longer than twenty minutes.
- The twenty minutesTreat it as a guide, not a rule; it depends on your pan and the wetness of the fruit. Test for set at 220F on a thermometer, or by the wrinkle test on a chilled saucer. Overshooting gives a stiff, caramel-tasting jam.
- Slow fire, then boilThe first gentle heating dissolves the sugar and brings up the scum, which you skim. Only after the sugar is fully dissolved should the heat go up to a rolling boil, or the jam will crystallise.
- "Put them into glasses"Small straight-sided preserving glasses, filled hot and traditionally sealed with brandied paper and a cover. With no processed seal, the jam relies on sugar alone; keep it refrigerated after filling, or follow current water-bath canning directions if you want shelf storage.
- YieldTwo pounds of fruit with two pounds of sugar gives about five half-pint jars.
Equal-weight jams like this one belong to the English preserving tradition that ran from the seventeenth century well into the nineteenth, when sugar was expensive enough to be treated as the preservative it is rather than merely a sweetener. The instruction to add red currant juice is practical folk chemistry predating any understanding of pectin: cooks knew that strawberries alone made a syrupy, sloppy preserve and that currants, gooseberries or apple parings corrected it, long before pectin was isolated and named in the early nineteenth century. "Scarlet" strawberries were the named class of the day, small and intensely flavoured; the large Fragaria ananassa hybrids that dominate modern markets were still being developed when recipes of this type were in wide circulation. The word "glasses" rather than "jars" is another period marker — jam was set into small footed or straight glasses and sealed at the top with paper, the screw-band jar being a later arrival.