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
Place the egg yolk in a cold bowl.
Work the yolk smooth with a wooden spoon.
Add the salt, pepper, and mustard; mix well.
Gradually stir in the oil, drop by drop.
When the sauce thickens, add a little lemon juice.
Continue alternating oil and lemon juice until finished.
Make in a cool place and stir in one direction only.
If the sauce curdles, start fresh with a new egg yolk and add a little fresh oil before incorporating the curdled mixture.
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 + peppertop 9% of all pairsSmell alikemoderateCooked together15,430 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Lemon + mustardtop 11% of all pairsSmell alikestrongCooked together3,816 recipes
Shared aroma: eucalyptol (eucalyptus, herbal).
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Egg + lemontop 19% of all pairsSmell alikelowCooked together44,316 recipes
Shared aroma: (e,e)-2,4-decadienal (fatty, deep fried).
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Egg + mustardtop 28% of all pairsSmell alikemoderateCooked together9,210 recipes
Shared aroma: (e)-2-octenal (fatty, green).
Egg and lemon barely smell alike, yet cooks put them together in 44,316 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
- Emulsifies the oil and water so the oil stays suspended as a thick sauce.
- Oil
- Provides the fat that forms the body and rich texture of the sauce.
- Lemon juice
- Adds acidity that brightens flavour and helps keep the emulsion stable.
- Mustard
- Acts as an extra emulsifier that helps the sauce hold together.
The step that matters
Adding the oil drop by drop. Oil added too quickly overwhelms the egg yolk, which cannot emulsify it, so the sauce curdles and separates. Adding oil slowly lets the yolk coat each droplet and build a stable emulsion.
Swap the mustard
How well each one fits the dish's main ingredients (egg, lemon, pepper):
- Spinachfits better
- Capsicumfits better
- Asparagusfits better
- Mustardthe original
Fit is the average pairing score against egg, 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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