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
Make the sauce
Mash the yolks of the hard-boiled eggs in a bowl.
Add mustard, pepper, coarse sea salt, vinegar, and salad oil, then mix well until smooth.
Stir in ketchup if desired.
Serve
Serve over 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).
-
Pepper + vinegartop 14% of all pairsSmell alikemoderateCooked together27,814 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
-
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
- Egg yolks
- Their fat and emulsifiers bind the oil and vinegar into a smooth, thick sauce.
- Mustard
- Its compounds help emulsify the oil and add a sharp, pungent flavour.
- Vinegar
- Adds acidity that brightens the sauce and balances the richness of the yolks and oil.
- Salad oil
- Supplies fat that gives the sauce a smooth, creamy body.
The step that matters
Mix well until smooth. Oil and vinegar separate unless the yolks and mustard are fully worked in. Thorough mixing builds a stable emulsion, so the sauce stays smooth rather than greasy or broken.
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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