Apple Snow

This is a Victorian uncooked whip: sweetened apple pulp beaten into raw egg white until it holds like snow. Two things in it put the recipe outside modern practice, and neither can be fixed by adjusting the method.

• The whites are never cookedThe mixture is whipped, dropped onto a glass dish and served as it stands. Nothing in the process brings the egg white to a temperature that would deal with Salmonella, and the dish would typically sit at room temperature while it was dressed and carried to table. A current recipe for apple snow should be used instead.
• The pinch of alumAlum here is potassium aluminium sulphate. The recipe gives no reason for it; the likeliest purpose is as a firming and whitening agent, alum having been used elsewhere to keep fruit firm and pale. It was a common nineteenth-century kitchen and bakery additive and was also, notoriously, used to adulterate bread. It has no place in a modern dessert and contributes nothing a properly beaten white does not.
• What "the pulp of roasted apples" meansWhole apples were baked until collapsing, then the flesh was scooped out and sieved. Half a pound of pulp is about 225 g, perhaps three medium cooking apples before roasting. Roasted pulp is drier than stewed, which would help it not slacken the foam, though the recipe says nothing about why roasting is specified.
• Half a pound of sugarThat is about 225 g against 225 g of apple pulp, an equal weight. Powdered sugar in a British book of this period means finely ground white sugar, not the cornflour-cut icing sugar sold today. Even by Victorian standards this is a very sweet whip, aimed at hard cooking apples.
• "Whip all together for an hour"The hour reflects hand beating with a whisk or a bundle of birch twigs into a broad bowl. It is a measure of labour, not of any chemical change, and no modern reading of the timing makes the finished dish any safer.
• ServingThe recipe directs only that the whip be dropped lightly onto a glass dish and served as it stands.