Why it works: Apple and lemon are a kitchen classic. They rank in the top 14% of all ingredient pairs, and cooks put them together in 7,551 recipes. Both carry trans-2-nonenal, which smells cardboard, fatty. The science ↓
Apple Pie
Ingredients
Directions
Make the filling
Grate the apples.
Combine them with eggs, sugar, lemon juice, and lemon zest in a saucepan.
Cook over medium heat until the mixture thickens.
If it doesn't thicken, stir in a little cornstarch.
Assemble and bake
Line pie plates with crust.
Fill with the apple mixture.
Bake until golden brown.
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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Apple + lemontop 14% of all pairsSmell alikemoderateCooked together7,551 recipes
Shared aroma: trans-2-nonenal (cardboard, fatty).
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Apple + sugartop 18% of all pairsSmell alikelowCooked together16,478 recipes
Shared aroma: beta-damascenone (apple, rose).
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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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Egg + sugartop 21% of all pairsSmell alikemoderateCooked together122,807 recipes
Shared aroma: 2-nonenal (fatty, green).
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
- Apples
- Provide the bulk of the filling and its tart, fruity flavour.
- Eggs
- Help thicken the filling as they cook and bind it together.
- Sugar
- Adds sweetness and helps balance the tartness of the apples and lemon.
- Lemon juice
- Adds acidity that brightens the flavour and keeps the apples from tasting flat.
- Cornstarch
- Thickens the filling as it heats if the mixture stays too loose.
The step that matters
Cooking the filling until it thickens. Eggs and starch set as the mixture heats, so it must reach a thick consistency before filling the crust. Undercooked filling stays runny and can make the crust soggy, while overcooking can cause the eggs to curdle.
Swap the apple
How well each one fits the dish's main ingredients (egg, sugar, lemon):
- Orangefits better
- Vanillafits better
- Limefits better
- Applethe original
Fit is the average pairing score against egg, sugar, lemon. 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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