Why it works: Pepper and lemon match in chemistry and in kitchens. They rank in the top 3% of all ingredient pairs, and cooks put them together in 27,047 recipes. Both carry trans-2-nonenal, which smells cardboard, fatty. The science ↓
Mayonnaise Sauce
Ingredients
Directions
Make the emulsion
In a bowl, beat the egg yolks.
Slowly add the olive oil until the mixture thickens and resembles butter.
Stir in the salt, then gradually add more olive oil.
Season and finish
Add the dry mustard and cayenne pepper.
Alternately mix in the vinegar and lemon juice until the sauce is thick enough to spread.
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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Pepper + lemontop 3% of all pairsSmell alikestrongCooked together27,047 recipes
Shared aroma: trans-2-nonenal (cardboard, fatty).
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Mustard + vinegartop 7% of all pairsSmell alikemoderateCooked together14,067 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Olive + lemontop 7% of all pairsSmell alikemoderateCooked together11,922 recipes
Shared aroma: 3-hexenal (apple, fruity).
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Olive + mustardtop 8% of all pairsSmell alikestrongCooked together5,950 recipes
Shared aroma: eucalyptol (eucalyptus, herbal).
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Mustard + peppertop 9% of all pairsSmell alikemoderateCooked together15,430 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Egg yolks
- Their lecithin emulsifies the oil and water so the sauce stays smooth and thick.
- Olive oil
- Forms the bulk of the sauce, providing richness and body once emulsified into the yolks.
- Vinegar
- Adds acidity that sharpens flavour and helps stabilise the emulsion.
- Lemon juice
- Adds bright acidity that balances the richness of the oil and yolks.
The step that matters
Adding the olive oil slowly. Oil must be dispersed into the yolks one drop at a time at first. Adding it too fast overwhelms the egg lecithin, so the emulsion breaks and the sauce turns runny and oily instead of thick.
Swap the mustard
How well each one fits the dish's main ingredients (egg, olive, pepper, vinegar, lemon):
- Capsicumfits better
- Spinachfits about as well
- Cucumberfits about as well
- Mustardthe original
Fit is the average pairing score against egg, olive, pepper, vinegar, lemon. 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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