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 Sauce
Ingredients
Directions
In a bowl, add the egg yolk.
Slowly add the oil drop by drop, mixing thoroughly after each addition.
Once a foundation is formed, you can add the remaining oil more quickly.
Stir in vinegar, mustard, and salt to taste.
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.
-
Vinegar + mustardtop 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 yolk
- Emulsifier that binds the oil and water so the sauce stays thick and smooth.
- Oil
- Fat that forms the body of the sauce once dispersed into droplets by the yolk.
- Vinegar
- Adds acidity that brightens flavor and helps stabilize the emulsion.
- Mustard
- Contains natural emulsifiers that help hold the oil droplets in suspension.
The step that matters
Adding the oil slowly at the start. Oil must be dispersed into tiny droplets coated by egg yolk proteins. Adding it too fast overwhelms the yolk, so the emulsion breaks and the sauce turns oily and runny.
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.
More mayonnaise recipes
You might also like
The free Flavor Lab newsletter: one surprising pairing a week and the molecular reason it works, in 60 seconds. No spam, unsubscribe anytime.
Prefer an account? Create a free account to save pairings and unlock the full chemistry.

Tomato Soup526 recipes
Brown Bread461 recipes
Mutton Broth292 recipes
Yorkshire Pudding264 recipes