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 ↓
Mayonnaise
Ingredients
Directions
Make the base
Beat the eggs in a bowl.
Add salt, sugar, mustard, and vinegar to the eggs.
In a saucepan, heat the butter and add the flour, stirring until smooth.
Gradually add the milk to the butter and flour mixture, bringing it to a boil.
Thicken and store
Slowly combine the hot mixture with the egg mixture, stirring continuously until it thickens like custard.
Once cool, transfer to wide-mouthed bottles and store in a cool place.
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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Vinegar + mustardtop 7% of all pairsSmell alikemoderateCooked together14,067 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Pepper + mustardtop 9% of all pairsSmell alikemoderateCooked together15,430 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Butter + flourtop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Flour + mustardtop 13% of all pairsSmell alikemoderateCooked together5,066 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
- Eggs
- Beaten eggs provide structure as they thicken the mixture like a custard.
- Butter
- Melted butter adds richness and a smooth, fatty mouthfeel.
- Flour
- Flour cooked with butter forms a roux that thickens the sauce.
- Milk
- Milk adds moisture and creaminess to the thickened base.
- Vinegar
- Vinegar adds acidity that gives the sauce a tangy flavour.
The step that matters
Combining the hot mixture with the eggs. Adding hot liquid to eggs too quickly can scramble them. Pour slowly while stirring constantly so the eggs warm gradually and thicken smoothly into a custard-like texture.
Swap the mustard
How well each one fits the dish's main ingredients (butter, flour, sugar, egg, pepper, milk, vinegar):
- Capsicumfits better
- Shallotfits about as well
- Mustardthe original
- Chivefits about as well
Fit is the average pairing score against butter, flour, sugar, egg, pepper, milk, vinegar. 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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