Why it works: Butter and flour are a kitchen classic. They rank in the top 12% of all ingredient pairs, and cooks put them together in 124,287 recipes. Both carry isobutyraldehyde, which smells malty, green. The science ↓
Lemon Pie
Ingredients
Directions
The book gives no oven temperature. The 350°F (175°C) in the steps was added when the recipe was transcribed, as a starting point.
Make the filling
Preheat the oven to 350°F (175°C).
In a bowl, mix ¾ cup sugar, 1 tablespoon butter, 3 egg yolks, 1 tablespoon flour, ⅔ cup water, ½ grated lemon rind, and juice of 1 lemon.
Pour the mixture into a pie crust and bake until set.
Top and finish
Beat 3 egg whites until light, adding 1 tablespoon sugar for each egg white to make meringue.
Flavor the meringue with lemon juice and spread it over the baked pie.
Return the pie to the oven until the meringue is slightly 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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Butter + flourtop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Sugar + flourtop 15% of all pairsSmell alikemoderateCooked together92,116 recipes
Shared aroma: phenylacetaldehyde (hawthorne, honey).
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Egg + flourtop 15% of all pairsSmell alikelowCooked together106,462 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Butter + lemontop 16% of all pairsSmell alikemoderateCooked together41,227 recipes
Shared aroma: 3-hexenal (apple, fruity).
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Flour + lemontop 17% of all pairsSmell alikemoderateCooked together30,404 recipes
Shared aroma: isobutyraldehyde (malty, green).
Butter and flour barely smell alike, yet cooks put them together in 124,287 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
- Egg yolks
- Thicken the filling as they set, giving the custard its rich body.
- Egg whites
- Whip into a foam that sets into the light, airy structure of the meringue.
- Sugar
- Sweetens the filling and helps stabilize the whipped egg white foam.
- Lemon juice
- Adds tart acidity that balances the sweetness of the filling and meringue.
- Flour
- Stabilizes the filling so it sets firmly rather than running when cut.
The step that matters
Bake the filling until set. Underbaked egg yolk filling stays runny and will not cut cleanly. Baking until just set coagulates the yolk proteins and thickens the filling, so it holds its shape under the meringue.
Swap the lemon
How well each one fits the dish's main ingredients (sugar, butter, egg, flour):
- Raisinfits better
- Vanillafits better
- Figfits about as well
- Lemonthe original
Fit is the average pairing score against sugar, butter, egg, flour. 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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