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
In a bowl, mix the yolks of two raw eggs with 1 teaspoon of dry mustard.
Gradually add 1 teacup of Lucca oil while whisking until the mixture is thick.
Thin the mixture with vinegar until it reaches the consistency of cream.
Stir in 1 teaspoon of salt.
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
- Emulsify the oil into the mixture and thicken the dressing as it is whisked.
- Lucca oil
- Forms the fat base of the dressing, giving richness and body once emulsified.
- Vinegar
- Thins the thickened emulsion and adds acidity to balance the richness.
The step that matters
Adding the oil gradually while whisking. Oil added too quickly cannot be absorbed by the egg yolk, so the emulsion breaks and the dressing separates instead of thickening. Adding it slowly in a thin stream lets the yolk lecithin surround the oil droplets and hold them in suspension.
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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