Why it works: Milk and lemon are a kitchen classic. They rank in the top 15% of all ingredient pairs, and cooks put them together in 19,053 recipes. Both carry 2-nonenal, which smells fatty, green. The science ↓
Plain Custard
Ingredients
Directions
Make the custard base
Boil the milk with sugar and lemon peel.
In a bowl, beat the eggs well.
Gradually pour the hot milk into the eggs, mixing well.
Strain the mixture through a sieve into cups.
Steam and set
Place the cups in a steamer with 1 inch of water.
Cook for about 12 minutes or until set.
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.
Photo for illustrative purposes only · Contact us to use it
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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Milk + lemontop 15% of all pairsSmell alikemoderateCooked together19,053 recipes
Shared aroma: 2-nonenal (fatty, green).
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Sugar + lemontop 18% of all pairsSmell alikelowCooked together53,532 recipes
Shared aroma: 2-nonenal (fatty, green).
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Milk + eggtop 18% of all pairsSmell alikemoderateCooked together88,785 recipes
Shared aroma: 2-nonenal (fatty, green).
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Milk + sugartop 18% of all pairsSmell alikelowCooked together77,875 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).
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
- Eggs
- Set the custard into a tender, sliceable structure as they cook.
- Milk
- Provides the liquid base that gives the custard its smooth, creamy body.
- Sugar
- Adds sweetness and softens the set custard's flavour.
The step that matters
Gradually pour the hot milk into the eggs. Adding hot milk slowly while whisking tempers the eggs, so they warm gently instead of scrambling. Pouring too fast can curdle the mixture and leave it grainy.
Swap the lemon
How well each one fits the dish's main ingredients (milk, sugar, egg):
- Vanillafits better
- Figfits about as well
- Raisinfits about as well
- Lemonthe original
Fit is the average pairing score against milk, 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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