Why it works: Mustard and vinegar are a kitchen classic. They rank in the top 7% of all ingredient pairs, and cooks put them together in 14,067 recipes. Both carry isobutyraldehyde, which smells malty, green. The science ↓
Egg Sauce
Ingredients
Directions
Mash the hard-boiled egg yolks in a bowl.
Add mustard, pepper, salt, vinegar, and salad oil, then mix until smooth and well combined.
Stir in ketchup if desired.
Serve with boiled fish.
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.
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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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Pepper + vinegartop 14% of all pairsSmell alikemoderateCooked together27,814 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
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Mustard + ketchuptop 17% of all pairsSmell alikemoderateCooked together331 recipes
Shared aroma: ethanol (alcoholic, ethereal).
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Vinegar + ketchuptop 21% of all pairsSmell alikelowCooked together737 recipes
Shared aroma: ethanol (alcoholic, ethereal).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Hard-boiled egg yolks
- Mashed yolks form the thick, creamy body of the sauce.
- Salad oil
- Adds fat that gives the sauce a smooth, rich texture.
- Vinegar
- Adds acidity that brightens the sauce and balances the rich yolks and oil.
- Mustard
- Adds sharp flavour and helps emulsify the oil into the yolks.
The step that matters
Mixing the oil and vinegar into the yolks. Adding the oil and vinegar gradually while mixing helps the fat disperse into the yolks as a stable emulsion. Dumping it in all at once can leave the sauce greasy or separated, so it should be mixed until smooth and well combined.
Swap the mustard
How well each one fits the dish's main ingredients (egg, pepper, vinegar, ketchup):
- Capsicumfits better
- Horseradishfits about as well
- Mustardthe original
- Shallotfits about as well
Fit is the average pairing score against egg, pepper, vinegar, ketchup. 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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