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Isinglass Jelly, Strawberry
Take a quart of fine ripe scarlet strawberries, and pour over them a pint of water that has boiled for twenty minutes with three-quarters of a pound of loaf sugar. The next day, drain off the syrup from the strawberries without bruising them, and, to increase the fruity flavour, add a little lemon-juice and half a pint of red currant juice. Clarify two ounces and a half of isinglass in a pint of water, and let it stand till nearly cold, then mix it with the fruit-juice and pour into moulds. It is desirable to place the moulds in ice. Probable cost, 2s. 10d., exclusive of fruit.
A cold-set fruit jelly from the era before packet gelatine, when clarity was the whole point of the dish. The strawberries are never cooked y are steeped overnight in hot syrup and then discarded, so all the flavour has to come out of them in that one soak.
- Isinglass to gelatineIsinglass is dried fish swim bladder, sold in leaves or shreds, and its setting power varied enormously by grade, so 2½ oz cannot be converted exactly. As a working figure, modern powdered gelatine is considerably stronger; around 1 oz (four sachets) to the roughly 2½ pints of total liquid here will give a jelly firm enough to unmould. Test a spoonful on a cold saucer before committing the whole batch.
- "Clarify"For isinglass this means soaking it, dissolving it in the water over gentle heat, and skimming or straining out the cloudiness ditionally with a whisked egg white raft. With modern gelatine the step is unnecessary; bloom it in cold water and dissolve it without boiling.
- Loaf sugarRefined cane sugar sold in a hard cone and broken up with sugar nippers. Ordinary granulated sugar is the direct replacement; ¾ lb is about 1⅔ cups.
- QuantitiesA quart of strawberries is roughly 1½ lb; a pint here is the imperial pint of 20 fl oz, so the water is about 570 ml. The finished volume comes to about 2½ imperial pints, near 1.4 litres, which fills a large mould and serves eight to ten.
- The overnight steepThe syrup is poured hot over raw fruit and left to stand. Do that in the refrigerator rather than a cool larder, and strain the syrup through a jelly bag or muslin without pressing queezing is what turns the jelly cloudy.
- Temperature when mixingLetting the dissolved isinglass stand until nearly cold before combining is the hinge of the recipe. Hot gelatine liquid poured into cold fruit juice sets in ropes and streaks; both should be cool but still fluid, around blood heat or below.
- Setting"Place the moulds in ice" means the refrigerator now. Allow four to six hours for a large mould, and dip it briefly in warm water to turn out.
- The costing2s. 10d. is pre-decimal shillings and pence and reflects the price of isinglass, which was expensive. It tells you nothing useful about cost today beyond the fact that the setting agent, not the fruit, was the luxury.
Isinglass was collagen extracted from the swim bladders of sturgeon, the best grades imported from Russia and sold in several grades; it was widely used as a setting agent for clear jellies and blancmanges in the English kitchen through much of the nineteenth century, alongside calves'-foot stock, and doubled as a fining agent in brewing, where it is still used. Cassell's, compiled for middle-class households in the 1870s and 80s, appeared as commercially prepared sheet and, later, powdered gelatine was displacing it, which is why so many jelly recipes of the period read as fussily as this one, with clarifying and skimming steps that packet gelatine made obsolete. The insistence on "fine ripe scarlet strawberries" and the addition of red currant juice reflects a practical problem rather than mere prettiness: strawberries alone give a pale, washed-out infusion, and currants supplied both the colour and the acidity that made the jelly taste of fruit instead of sugar.