Why it works: Sugar and lemon are a kitchen classic. They rank in the top 18% of all ingredient pairs, and cooks put them together in 53,532 recipes. Both carry 2-nonenal, which smells fatty, green. The science ↓
Cake Icing
Ingredients
Directions
Make the icing
Sift the icing sugar through a fine sieve into a bowl.
Make a well in the sugar and add the egg whites and lemon juice. Mix well with a wooden spoon until soft.
Ice the cake
Use a knife dipped in water to spread two layers of icing on the cake.
For the third layer, boil the loaf sugar and water together for 15-20 minutes until syrupy. Stir the syrup until nearly cold and pour over the cake.
Once dry, decorate with the first icing using a piping bag.
Transcribed from a scanned cookbook and modernised for today's kitchens. Where the book gave no heat or time, or said "a moderate oven", the temperatures and times here may be modern equivalents rather than the book's own figures.
Explore the science
The flavor team
The pairs that carry this dish. Each one is judged two ways: how much their aromas overlap, and how often cooks already put them together.
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Sugar + lemontop 18% of all pairsSmell alikelowCooked together53,532 recipes
Shared aroma: 2-nonenal (fatty, green).
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Egg + lemontop 19% of all pairsSmell alikelowCooked together44,316 recipes
Shared aroma: (e,e)-2,4-decadienal (fatty, deep fried).
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Sugar + eggtop 21% of all pairsSmell alikemoderateCooked together122,807 recipes
Shared aroma: 2-nonenal (fatty, green).
Sugar and lemon barely smell alike, yet cooks put them together in 53,532 recipes: they work on texture and structure more than aroma.
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Icing sugar
- Provides sweetness and the bulk that gives the frosting its body.
- Egg whites
- Add structure and help the icing set firm and smooth.
- Loaf sugar
- Boiled with water to make a syrup that forms a glossy, sweet top layer.
- Lemon juice
- Adds acidity that balances the sweetness and brightens the flavour.
The step that matters
Stir the syrup until nearly cold before pouring. Syrup poured while very hot will run off the cake and soak in rather than coat it. Cooling it until nearly cold lets it thicken slightly so it stays on the surface.
Swap the lemon
How well each one fits the dish's main ingredients (sugar, egg):
- Vanillafits better
- Raisinfits about as well
- Lemonthe original
- Datesfits less well
Fit is the average pairing score against sugar, egg. Candidates are from the same food group and used in at least 100 recipes.
“What each ingredient does” and “The step that matters” were written by Claude from this recipe’s own method and reviewed in samples by CompKitchen.
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