Jaune Mange
Take two ounces of isinglass, turn over it one gill of cold water and let it stand a quarter of an hour; then add a pint of boiling water, and set the dish in a pan of boiling water until it is all dissolved; add to it the grated rind of two lemons, with the boiling water and also squeeze in their juice, sweeten to taste; stir in the beaten yolks of four eggs and let it simmer, stirring all the time for five minutes. Take from the fire, place in a pan of cold water and turn into it two wine-glasses of white wine; strain it through a jelly strainer into a mould and place it on the ice, whip the whites of the eggs with a little sugar for a sauce, if sauce is required.
A lemon and white wine jelly enriched with egg yolks — the yellow counterpart to blancmange. The whole thing hinges on gentle heat: the yolks must thicken without curdling, and the wine goes in only after the mixture is off the fire.
- Isinglass to gelatinIsinglass is a collagen extract from fish swim bladders, and old commercial grades varied enormously in strength, so two ounces is not a reliable figure. Work from modern practice instead: about 2 to 3 teaspoons of powdered gelatin per pint of liquid gives a jelly firm enough to unmould, and the finished mixture here runs to roughly three cups once the wine is added.
- Gill and wine-glassA gill is half a cup. A wine-glass in this period is about 2 fluid ounces, so two wine-glasses is about half a cup of white wine.
- The bain-marie is not optionalThe bain-marie -- "Set the dish in a pan of boiling water" is specified for dissolving the isinglass, and the same water bath is the safest way to handle the yolk stage that follows, though the recipe does not say so outright. Four yolks in a thin, acidic, sugared liquid can curdle quickly over direct heat; held at a simmer in a water bath and stirred, they thicken smoothly in the five minutes given.
- Add the wine coldThe wine goes in after the pan is set in cold water, and for good reason — pouring alcohol and additional acid into a hot yolk mixture is the fastest way to make it break. The straining step catches any curd and the grated rind.
- Setting"Place it on the ice" is a nineteenth-century refrigerator: the mould buried in an ice bath or an icebox. Four to five hours chilled, or overnight, gives a clean turn-out; dip the mould briefly in warm water to release it.
- The egg-white sauce is rawWhites whipped with sugar and served uncooked carry a real salmonella risk, which is why this style of sauce has largely disappeared. Pasteurized whites in the carton whip acceptably if you want it; otherwise serve the jelly with cream.
- Sweetening and yield"Sweeten to taste" with two lemons' worth of juice and rind means more sugar than instinct suggests — start around half a cup and taste while the mixture is still warm, since chilled jellies read less sweet. The quantity fills a one-quart mould and serves six.
Jaune mange is simply "yellow eating" set against blancmange, "white eating" — the pale almond-and-cream jelly that had been a fixture of English and French cookery since the medieval period. The yellow version, coloured and enriched by egg yolks and flavoured with lemon and wine, appears in English-language cookbooks by the early nineteenth century and remained a standard supper-table dessert through the Victorian era. Its presence in a household book of this sort reflects the era's enthusiasm for moulded jellies, which depended on isinglass or on stock boiled down from calves' feet; both were laborious and unpredictable, and both were largely displaced by packaged powdered gelatin, after which the clear moulded jelly stopped being a mark of a skilled kitchen and became an everyday convenience.