Why it works: Lemon and apple 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 ↓
Lemon Pie
Ingredients
Directions
The book gives no oven temperature. The 400°F (200°C) in the steps was added when the recipe was transcribed, as a starting point.
Prepare the filling
Grate the rind and strain the juice of the lemons.
Core, pare, and chop the apple finely.
Pound the soda cracker very fine and mix with melted butter.
Combine the lemon rind, juice, and chopped apple with the sugar.
Make the custard
Beat the yolks of the eggs until thick and frothy.
Beat the whites until stiff.
Fold the beaten yolks and whites into the lemon, apple, and sugar mixture.
Mix in the buttered cracker crumbs.
Pour the mixture into a pie crust.
Bake at 400°F (200°C) for 20 minutes or until the crust is done.
Top and finish
Beat the egg whites with 3 tablespoons of sugar until stiff.
Spread the meringue over the pie.
Return to the oven until the meringue is lightly browned.
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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Lemon + appletop 14% of all pairsSmell alikemoderateCooked together7,551 recipes
Shared aroma: trans-2-nonenal (cardboard, fatty).
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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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Lemon + buttertop 16% of all pairsSmell alikemoderateCooked together41,227 recipes
Shared aroma: 3-hexenal (apple, fruity).
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Butter + eggtop 17% of all pairsSmell alikemoderateCooked together118,967 recipes
Shared aroma: decanal (soap, orange peel).
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Butter + sugartop 17% of all pairsSmell alikemoderateCooked together98,233 recipes
Shared aroma: guaiacol (smoky, sweet).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Eggs
- Yolks thicken the filling and whites lighten it and help it set.
- Lemons
- Provide the tart flavour and aromatic oils from the rind, plus acidic juice.
- Sugar
- Sweetens the filling and, in the meringue, stabilises the whipped whites.
- Butter
- Adds richness and fat that carries flavour and gives the cracker crumbs a tender texture.
- Soda cracker
- Crumbs add body to the filling, helping it hold together as it bakes.
- Tart apple
- Adds moisture and body, with tartness that balances the sugar.
The step that matters
Beating the egg whites until stiff. Whites must be beaten to stiff peaks without overbeating, since air bubbles provide lift and structure. Under-whipped whites deflate and make the meringue weep, while overbeaten whites turn grainy and dry.
Swap the apple
How well each one fits the dish's main ingredients (lemon, butter, sugar, egg):
- Vanillafits better
- Orangefits better
- Raspberryfits better
- Applethe original
Fit is the average pairing score against lemon, butter, 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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