Why it works: Lemon and butter are a kitchen classic. They rank in the top 16% of all ingredient pairs, and cooks put them together in 41,227 recipes. Both carry 3-hexenal, which smells apple, fruity. The science ↓
Old-fashioned Lemon-custard Pie
Ingredients
Directions
The book says “a quick oven”. The 400°F (200°C) in the steps is the modern equivalent, not the book's own figure.
Make the custard
Beat the egg yolks and powdered sugar until creamy.
Add the 4 egg whites, one at a time, beating until light.
Cream the butter.
Gradually mix in the egg mixture.
Place the bowl over a pan of boiling water.
Stir continuously until thickened.
Remove from heat.
Let cool.
Bake the crust
Line 2 deep pie dishes with flaky pie crust.
Bake at 400°F (200°C) for 15 minutes.
Fill the crusts with the lemon custard.
Press down any air bubbles.
Make the meringue and finish
Beat the 6 egg whites until foamy.
Gradually add 6 tablespoons of powdered sugar, beating until stiff and glossy.
Spread the meringue over the custard.
Sift powdered sugar on top.
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 + buttertop 16% of all pairsSmell alikemoderateCooked together41,227 recipes
Shared aroma: 3-hexenal (apple, fruity).
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Egg + buttertop 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).
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Lemon + sugartop 18% of all pairsSmell alikelowCooked together53,532 recipes
Shared aroma: 2-nonenal (fatty, green).
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Lemon + eggtop 19% of all pairsSmell alikelowCooked together44,316 recipes
Shared aroma: (e,e)-2,4-decadienal (fatty, deep fried).
Lemon and sugar 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
- Eggs
- Yolks thicken the custard as they set, and whites whip into the foam that forms the meringue.
- Butter
- Adds fat for richness and a smooth, tender texture in the custard.
- Powdered sugar
- Sweetens the custard and dissolves smoothly, and it helps stabilize the whipped meringue.
- Lemon juice
- Provides the sharp acidity that gives the custard its bright flavor.
- Lemon rind
- Adds fragrant lemon oils that contribute aroma.
The step that matters
Stir the custard until thickened over the water. Egg proteins set gently as they heat. If the heat is too high or stirring stops, they can curdle into grainy lumps instead of a smooth, thick custard.
Swap the lemon
How well each one fits the dish's main ingredients (egg, butter, sugar):
- Vanillafits better
- Lemonthe original
- Raisinfits about as well
- Figfits about as well
Fit is the average pairing score against egg, butter, sugar. 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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