Why it works: Onion and mustard match in chemistry and in kitchens. They rank in the top 6% of all ingredient pairs, and cooks put them together in 9,259 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
A Simple Salad Dressing
Ingredients
Directions
In a bowl, mix the olive oil, grated onion, salt, pepper, and mustard, then stir well to combine.
Add the vinegar and mix again.
Pour the dressing over the salad.
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.
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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Onion + mustardtop 6% of all pairsSmell alikestrongCooked together9,259 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Mustard + vinegartop 7% of all pairsSmell alikemoderateCooked together14,067 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Olive + mustardtop 8% of all pairsSmell alikestrongCooked together5,950 recipes
Shared aroma: eucalyptol (eucalyptus, herbal).
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Olive + oniontop 8% of all pairsSmell alikemoderateCooked together29,779 recipes
Shared aroma: 2,4-decadienal (seaweed).
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Pepper + mustardtop 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
- Olive oil
- Provides the fat base and a smooth, rich mouthfeel that carries the other flavors.
- Vinegar
- Adds acidity that brightens the dressing and balances the richness of the oil.
- Mustard
- Helps oil and vinegar hold together as an emulsion, and adds a sharp, savory bite.
- Grated onion
- Contributes aroma and a sharp savory flavor that moves through the dressing.
The step that matters
Add the vinegar and mix again. Oil and vinegar naturally separate. Mixing thoroughly after adding the vinegar breaks the oil into tiny droplets, creating a more stable, evenly flavored emulsion that clings better to the salad.
Swap the onion
How well each one fits the dish's main ingredients (olive, pepper, mustard, vinegar):
- Capsicumfits better
- Lettucefits better
- Horseradishfits better
- Onionthe original
Fit is the average pairing score against olive, pepper, mustard, 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.
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