Why it works: Butter and milk are a kitchen classic. They rank in the top 7% of all ingredient pairs, and cooks put them together in 81,283 recipes. Both carry (z)-4-heptenal, which smells biscuit, cream. The science ↓
Citron Cake
Ingredients
Directions
The book says “a moderate oven”. The 350°F (175°C) in the steps is the modern equivalent, not the book's own figure.
Prepare
Preheat the oven to 350°F (175°C) and grease a baking pan.
Make the batter
Cream the butter and gradually add the sugar, mixing well.
Beat in the eggs, reserving the white of one for frosting.
Gradually add the milk, then mix in the flour and baking powder.
Stir in the chopped citron.
Bake
Pour the batter into the prepared pan and bake for about 30 minutes.
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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Butter + milktop 7% of all pairsSmell alikemoderateCooked together81,283 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
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Butter + flourtop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Milk + flourtop 14% of all pairsSmell alikelowCooked together78,219 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).
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
- Butter
- Creams with sugar to trap air and add richness and tenderness to the crumb.
- Eggs
- Add structure and richness as they set, and bind the batter together.
- Flour
- Forms the main structure of the cake as its proteins set during baking.
- Baking powder
- Releases gas in the batter so the cake rises and becomes light.
- Citron
- Adds candied fruit flavour and chewy pieces throughout the cake.
The step that matters
Gradually add the sugar while creaming the butter. Sugar crystals cut into the butter as it is beaten, trapping air that gives the batter lift. Adding it gradually lets the mixture stay smooth and emulsified, so the cake bakes up light rather than dense.
“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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