Orange Icing
Whites of two eggs, twelve tablespoonfuls sugar, the juice of two oranges and rind of one.
A three-line uncooked icing of the kind that fills nineteenth-century supper chapters, where a plain cake was iced at the table rather than baked with frosting. It is not safe to make today, and the notes below explain why, along with what the measurements actually mean.
- Raw egg white is the problemNothing in this recipe is heated. The whites are beaten with sugar and juice and spread on a cooled cake, so any Salmonella present in the shell eggs stays alive in the finished icing. Unlike a boiled or Italian meringue, there is no stage at which the mixture reaches a temperature that would reduce that risk, and the icing may sit at room temperature for hours or days afterwards. Use a current icing recipe instead.
- Acid does not make it safeThe orange juice lowers the pH somewhat, and old cookery writers treated citrus and vinegar as preservatives. Fruit-juice acidity is nowhere near strong enough or reliable enough to sterilise raw egg white, and it should not be read as a safeguard here.
- What "twelve tablespoonfuls sugar" meansTwelve tablespoons is three-quarters of a cup by modern measure, though period spoons were not standardised. The sugar type is unstated; uncooked icings of this period were often made with pulverised or powdered sugar, which dissolves cold, while granulated would stay gritty. The original gives no way to be certain which the author intended.
- Rind means zestGrate only the coloured outer layer of one orange. The white pith beneath is bitter and will carry through a sugar icing very noticeably.
- The proportions are looseThe juice of two oranges is a great deal of liquid for two whites and three-quarters of a cup of sugar. The recipe fixes the sugar quantity and gives no further guidance on consistency.
Orange icing belongs to the long era before commercial confectioners' sugar and stand mixers, when "icing" often meant egg white beaten stiff with sifted sugar and flavoured with whatever was to hand: rose water, lemon, vanilla, or in this case oranges, which by the later nineteenth century were reaching northern cities in greater quantity by rail and steamer. The method also explains the recipe's brevity: uncooked icing needed no thermometer, no sugar syrup and no fire.