Mock Ice
1152. Dissolve half an ounce of isinglass in a breakfast cup of hot water; beat up a pot of strawberry or any other preserve with a pint of cream, pass it through a sieve, add the juice of a lemon and a teacupful of sugar, then add the isinglass when nearly cold, whisk it together, and when it begins to thicken put it in a mould.
Another Mock Ice. - Dissolve one ounce of isinglass in a little water, let it strain and cool. Put the juice of three lemons, or half a pint of fruit jelly or fruit to one pint of cream, with some sugar-whisk, and add the cooled isinglass. Whisk again well, and pour into moulds.
An uncooked cream jelly set with isinglass and served cold from a mould — no freezing is involved despite the name. Two versions are given in the same entry; both work on the same principle.
- Isinglass, and what to use insteadIsinglass is a gelatine extracted from fish swim bladders, sold in sheets or shreds and soaked before use. Its setting strength varied by grade, so no exact equivalence is possible; for the first version (a pint of cream plus a pot of preserve, which comes to well over a quart of mixture) start with about 2 envelopes of powdered gelatine, or the same weight in leaf gelatine, for a spoonable set.
- The hinge: temperature of the gelatineAdd the dissolved isinglass when it is cool but still fluid, and have the cream mixture at cool room temperature rather than fridge-cold. Hot gelatine thins the whisked cream and cold gelatine seizes into threads that will not disperse.
- Imperial measuresA pint here is the imperial 20 fl oz, not 16. A breakfast cup is around 8 to 10 fl oz; a teacupful is nearer 6 fl oz, so the sugar in the first version is roughly 3/4 to 1 cup — taste and cut it back if the preserve is already sweet.
- A pot of preserveJam was commonly potted in roughly 1 lb pots, so "a pot" is probably about that. Half that is plenty against a pint of cream unless you want a very sweet, dense result.
- SievingPass the beaten preserve and cream through the sieve before the gelatine goes in, as the recipe directs. The sieve is there to catch strawberry pips and fruit fibre; skip it only if you want a rougher texture.
- WhiskingThe cream should be whisked to a soft, barely holding foam rather than stiff peaks. Over-whisked cream that then has acidic fruit and lemon juice folded through it turns grainy and can split.
- Setting and unmouldingFill the mould once the mixture visibly thickens and chill at least 4 hours, preferably overnight. To turn out, dip the mould briefly in warm water and invert onto a wetted plate.
- YieldThe first version, with a full pot of preserve, makes upwards of a quart and a half; the second, with half a pint of jelly, makes rather less. Serve in the small portions such a rich sweet expects.