Why it works: Milk and butter 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 ↓
Boiled Salad Dressing
Ingredients
Directions
Scald the milk in a double boiler.
In a bowl, blend the flour, mustard, salt, sugar, and cayenne.
Add the mixture to the slightly beaten yolks of the eggs.
Slowly pour the hot milk over the egg mixture, stirring constantly.
Return the mixture to the double boiler and cook until it thickens.
Slowly add the vinegar and butter, stirring to combine.
Whip in the beaten egg whites a little at a time.
Strain the dressing into glasses or glass jars.
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 + buttertop 7% of all pairsSmell alikemoderateCooked together81,283 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
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Mustard + vinegartop 7% of all pairsSmell alikemoderateCooked together14,067 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Mustard + peppertop 9% of all pairsSmell alikemoderateCooked together15,430 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Flour + buttertop 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).
Flour and butter 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
- Yolks thicken the dressing as they cook, and whites add lightness when whipped in.
- Flour
- Starch thickens the milk mixture so the dressing becomes smooth and body-rich.
- Milk
- Forms the liquid base that the eggs and flour cook into a custard-like dressing.
- Vinegar
- Adds acidity that gives the dressing its tangy, sharp flavor.
- Butter
- Adds fat that softens the dressing's flavor and gives a richer mouthfeel.
The step that matters
Return the mixture to the double boiler and cook until it thickens. Egg yolks can curdle or scramble if overheated. Gentle, indirect heat in a double boiler, with constant stirring, lets the starch and yolk proteins thicken the dressing smoothly.
Swap the mustard
How well each one fits the dish's main ingredients (milk, flour, sugar, pepper, egg, vinegar, butter):
- Capsicumfits better
- Shallotfits about as well
- Mustardthe original
- Chivefits about as well
Fit is the average pairing score against milk, flour, sugar, pepper, egg, vinegar, butter. 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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