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Isinglass Jelly, Currant and Raspberry
Bruise in a jar two pounds of red and one pound of white currants with a pint of red raspberries; place the jar in boiling water to extract the juice. Boil three-quarters of a pint of water, two ounces of isinglass, and a pound of loaf sugar together, allow both the fruit juice, when strained, and the sweetened isinglass to cool, then mix equal quantities, pour into shapes and place the jelly in ice. Probable cost of isinglass, 1s. per ounce.
A Victorian fruit jelly that depends on two things a modern cook has to translate: isinglass, and the absence of a refrigerator.
- IsinglassIsinglass is a setting agent made from the dried swim bladders of fish, sold in leaf or shred form and slower to dissolve than modern gelatin. Powdered or leaf gelatin is the usual replacement, but the quantities do not transfer directly: 2 oz of isinglass is not 2 oz of gelatin, and considerably less modern gelatin will set the same volume. Test a small quantity before committing the batch.
- Loaf sugarSold as a hard cone to be broken and crushed, loaf sugar was the most refined sugar available and prized for clear jellies. Ordinary granulated sugar is the equivalent; a pound is about 2 1/4 cups.
- Extracting the juiceThe jar standing in boiling water is a water bath — a covered jar or bowl set in a pan of simmering water for half an hour or so. It draws juice out gently without the scorching or scum that direct heat produces, which is what keeps the finished jelly bright.
- Strain, then leave it aloneFor a clear jelly the strained juice must drip through a scalded jelly bag or a double layer of muslin without being pressed or squeezed. Forcing it pushes pulp through and the jelly sets cloudy — the one step that decides whether this looks like the book intends.
- Mix warm, not hot or coldMix while still pourable -- The recipe has both liquids cooled before they are mixed. Cool here means lukewarm rather than cold: if either begins to set before they meet you get streaks and lumps, so combine them while both are still fluid.
- Equal quantitiesMixing equal quantities may well leave juice over, depending on how much the fruit yields. Sweeten and chill any surplus as a drink rather than tipping it in and unbalancing the set.
- "Place the jelly in ice"This means packing the moulds in an ice pail, the usual method of rapid chilling in the period. The refrigerator does the same job: several hours for small moulds, overnight for a large one.
- YieldYield depends on the fruit, but the sweetened isinglass alone comes to something over a pint, with an equal quantity of juice added to it. To turn it out, dip the mould briefly in warm water and invert onto a wetted plate so the jelly can be slid into place.
Isinglass reached British kitchens as an import — much of it Russian, from sturgeon — and was valued for setting jellies clear at a time when the alternative was boiling down calves' feet for hours to make your own stock of gelatin. Cassell's quotes it at a shilling an ounce, which places this among the more expensive things a Victorian cook could put on a table: two ounces here represents real money. Isinglass was also long used to fine beer and wine, and it survives in that role today far more than in the kitchen, since commercially manufactured gelatin, cheaper and more reliable, largely displaced it for jellies. The fruit pairing is the standard English one: red currants bring acidity and pectin, white currants soften the colour, and raspberries supply the perfume, all three ripening together in the summer garden.