Why it works: Sugar and lemon are a kitchen classic. They rank in the top 18% of all ingredient pairs, and cooks put them together in 53,532 recipes. Both carry 2-nonenal, which smells fatty, green. The science ↓
Lemon Pie
Ingredients
Directions
Make the lemon filling
Stir cornstarch in a little cold water.
Add boiling water and let it boil.
Stir in sugar, egg yolks, lemon rind, and lemon juice.
Pour the mixture into the pie crust and bake.
Top and finish
Beat egg whites with powdered sugar until stiff.
Spread the egg white mixture on top of the pie.
Return the pie to the oven and 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.
-
Sugar + lemontop 18% of all pairsSmell alikelowCooked together53,532 recipes
Shared aroma: 2-nonenal (fatty, green).
-
Egg + lemontop 19% of all pairsSmell alikelowCooked together44,316 recipes
Shared aroma: (e,e)-2,4-decadienal (fatty, deep fried).
-
Sugar + eggtop 21% of all pairsSmell alikemoderateCooked together122,807 recipes
Shared aroma: 2-nonenal (fatty, green).
Sugar and lemon 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
- Cornstarch
- Thickens the lemon mixture as it boils, giving the filling body.
- Egg yolks
- Enrich and thicken the filling, adding richness and a smooth set.
- Egg whites
- Whipped with powdered sugar to form a stiff, airy topping that browns in the oven.
- Lemon juice
- Provides the sharp acidity that defines the pie's flavor and balances the sugar.
The step that matters
Bring the cornstarch mixture to a boil. Cornstarch only thickens fully once it reaches a boil, so the filling must be brought to a full boil before the other ingredients are added to avoid a thin, runny filling.
Swap the lemon
How well each one fits the dish's main ingredients (sugar, egg):
- Vanillafits better
- Raisinfits about as well
- Lemonthe original
- Datesfits less well
Fit is the average pairing score against 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.
More lemon pie recipes
You might also like
Lemon Cake228 recipes
Lemon Ice147 recipes
Lemon Sherbet103 recipes
Lemon Custard64 recipesThe free Flavor Lab newsletter: one surprising pairing a week and the molecular reason it works, in 60 seconds. No spam, unsubscribe anytime.
Prefer an account? Create a free account to save pairings and unlock the full chemistry.