Why it works: Lemon and pepper 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
Put the yolk of a raw egg into a cold bowl and beat it well with a silver fork.
Add 2 teaspoons of coarse sea salt and 1 teaspoon of powdered mustard; mix well for a minute.
Slowly add ½ cup of good olive oil, alternating with a few drops of vinegar until it thickens.
Once thick, switch to adding a few drops of lemon juice instead of vinegar.
When the egg has absorbed the oil, add a pinch of cayenne pepper and 1½ teaspoons of vinegar.
Taste and adjust seasoning as needed.
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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Lemon + peppertop 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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Mustard + olivetop 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 yolk
- Emulsifies the oil and water so the sauce thickens and holds together.
- Olive oil
- Provides the fat that, dispersed into droplets, forms the body of the sauce.
- Vinegar
- Adds acidity that brightens flavour and helps stabilise the emulsion.
- Powdered mustard
- Its natural emulsifiers help the oil and egg stay blended and stable.
The step that matters
Adding the oil slowly. Oil must be added a few drops at a time at first so the yolk can break it into tiny droplets. Adding it too fast overwhelms the yolk, and the sauce splits into a greasy, runny mixture that will not thicken.
Swap the mustard
How well each one fits the dish's main ingredients (egg, olive, vinegar, lemon, pepper):
- Capsicumfits better
- Spinachfits about as well
- Cucumberfits about as well
- Mustardthe original
Fit is the average pairing score against egg, olive, vinegar, lemon, 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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