Why it works: Apple and butter are a kitchen classic. They rank in the top 14% of all ingredient pairs, and cooks put them together in 8,706 recipes. Both carry trans-2-nonenal, which smells cardboard, fatty. The science ↓
Apple Soup
Ingredients
Directions
Prepare
Peel and chop the apple.
Cook and strain
Cook the apple and onion in the water until tender.
Rub the mixture through a sieve.
Finish and serve
Return to the saucepan, add butter, seasoning, and sugar.
Thicken the soup with cornflour and serve.
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.
Photo for illustrative purposes only · Contact us to use it
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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Apple + buttertop 14% of all pairsSmell alikemoderateCooked together8,706 recipes
Shared aroma: trans-2-nonenal (cardboard, fatty).
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Onion + buttertop 15% of all pairsSmell alikemoderateCooked together42,912 recipes
Shared aroma: decanal (soap, orange peel).
-
Sugar + buttertop 17% of all pairsSmell alikemoderateCooked together98,233 recipes
Shared aroma: guaiacol (smoky, sweet).
-
Apple + sugartop 18% of all pairsSmell alikelowCooked together16,478 recipes
Shared aroma: beta-damascenone (apple, rose).
-
Apple + oniontop 19% of all pairsSmell alikemoderateCooked together3,206 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Apple and sugar barely smell alike, yet cooks put them together in 16,478 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
- Cooking apple
- Provides the main body and flavour of the soup once cooked and puréed.
- Onion
- Adds savoury depth that balances the sweetness of the apple.
- Butter
- Adds richness and a smoother mouthfeel to the finished soup.
- Cornflour
- Thickens the puréed soup by swelling in liquid when heated.
The step that matters
Thicken the soup with cornflour. Cornflour must be cooked in the hot liquid to swell and thicken it. Adding it to cold liquid or boiling it too briefly can leave lumps or a thin soup with a starchy taste.
Swap the onion
How well each one fits the dish's main ingredients (apple, sugar, butter):
- Sweet potatofits better
- Capsicumfits better
- Parsnipfits better
- Onionthe original
Fit is the average pairing score against apple, sugar, butter. 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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