Name: Yellow Icing
Ingredients: peel of 1 or more oranges; 2 cups sugar; 2 egg whites; juice of 1 orange

Why it works: Orange and sugar are a kitchen classic. They rank in the top 20% of all ingredient pairs, and cooks put them together in 19,212 recipes. Both carry beta-damascenone, which smells apple, rose. The science ↓

Yellow Icing

Ingredients

peel of 1 or more oranges
2 cups sugar
2 egg whites
juice of 1 orange

Directions

Prepare the colour

Grate the peel of the oranges and place it in a fine cloth.
Tie the cloth and boil it in a few spoonfuls of water.
Squeeze the cloth to extract the colour.

Make the icing

In a saucepan, combine the extracted colour with sugar, egg whites, and orange juice.
Stir until well mixed and smooth.

Recipe from a historical cookbook (Internet Archive).

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.

Orange + sugartop 20% of all pairs

Smell alikelow

Cooked together19,212 recipes

Shared aroma: beta-damascenone (apple, rose).
Sugar + eggtop 21% of all pairs

Smell alikemoderate

Cooked together122,807 recipes

Shared aroma: 2-nonenal (fatty, green).
Orange + eggtop 31% of all pairs

Smell alikelow

Cooked together10,696 recipes

Shared aroma: 2,4-decadienal (seaweed).

Orange and sugar barely smell alike, yet cooks put them together in 19,212 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

Sugar: Provides sweetness and the bulk that gives the icing its body.
Egg whites: Add structure and help the icing set smooth and glossy.
Orange peel: Supplies the colour and aroma of the orange.
Orange juice: Adds acidity and fresh citrus flavour, and moisture to the icing.