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 ↓
Salad Dressing
Ingredients
Directions
Prepare the yolks
Boil the eggs hard, then cool them.
Rub the yolks smooth in a mortar with the mustard and salt.
Make the dressing
Slowly add the oil while stirring continuously.
Gradually stir in the vinegar, drop by drop, until it reaches a creamy consistency.
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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Mustard + vinegartop 7% of all pairsSmell alikemoderateCooked together14,067 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Egg + mustardtop 28% of all pairsSmell alikemoderateCooked together9,210 recipes
Shared aroma: (e)-2-octenal (fatty, green).
-
Egg + vinegartop 33% of all pairsSmell alikelowCooked together12,922 recipes
Shared aroma: acetic acid (sour, vinegar).
Egg and vinegar barely smell alike, yet cooks put them together in 12,922 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
- Egg yolks
- Their fat and lecithin emulsify the oil and vinegar into a smooth, creamy dressing.
- Salad oil
- Forms the fat phase of the emulsion, giving body and richness to the dressing.
- Vinegar
- Adds acidity that balances the richness of the oil and yolks.
- Raw mustard
- Its natural emulsifiers help stabilise the emulsion and add sharpness.
The step that matters
Adding the oil and vinegar slowly. Oil must be added gradually while stirring so droplets disperse finely and the yolks can bind them. Adding too much at once makes the emulsion break and the dressing separate and turn oily.
Swap the mustard
How well each one fits the dish's main ingredients (egg, vinegar):
- Cucumberfits about as well
- Mustardthe original
- Capsicumfits about as well
- Shallotfits less well
Fit is the average pairing score against egg, 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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