Why it works: Vinegar and mustard 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 ↓
Mayonnaise
Ingredients
Directions
Make the emulsion
In a bowl, whisk the egg yolk until smooth.
Slowly add the oil while whisking continuously until the mixture thickens.
Season and finish
Stir in the vinegar, mustard, pepper, and salt.
Adjust seasoning to taste.
For variations, add chopped herbs, truffles, or curry as desired.
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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Vinegar + mustardtop 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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Vinegar + peppertop 14% of all pairsSmell alikemoderateCooked together27,814 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
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Egg + mustardtop 28% of all pairsSmell alikemoderateCooked together9,210 recipes
Shared aroma: (e)-2-octenal (fatty, green).
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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 yolk
- Lecithin in the yolk emulsifies the oil and water so the sauce thickens and holds together.
- Oil
- Forms the bulk of the sauce, giving it richness and a thick, creamy body once emulsified.
- Vinegar
- Adds acidity that brightens the flavour and helps balance the richness of the oil.
- Mustard
- Acts as a second emulsifier that helps keep the oil and yolk stable and well blended.
The step that matters
Slowly add the oil while whisking continuously. Oil must be dispersed in tiny droplets as it is added. Adding it too fast overwhelms the yolk's emulsifier, so the mixture breaks and fails to thicken.
Swap the mustard
How well each one fits the dish's main ingredients (egg, vinegar, pepper):
- Capsicumfits better
- Mustardthe original
- Cucumberfits about as well
- Cabbagefits less well
Fit is the average pairing score against egg, vinegar, pepper. 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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