Why it works: Cucumber and onion match in chemistry and in kitchens. They rank in the top 8% of all ingredient pairs, and cooks put them together in 6,050 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
Cucumber Catsup
Ingredients
Directions
Prepare
Pare and grate the cucumbers and onions.
Add the vinegar, black pepper, and coarse sea salt, then stir together thoroughly.
Rest and store
Let the mixture stand for a few hours.
Transfer to bottles or glass jars for storage.
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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Cucumber + oniontop 8% of all pairsSmell alikestrongCooked together6,050 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Cucumber + vinegartop 8% of all pairsSmell alikemoderateCooked together4,734 recipes
Shared aroma: 2-methylbutyl acetate (fruit).
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Onion + peppertop 11% of all pairsSmell alikemoderateCooked together68,474 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Cucumber + peppertop 12% of all pairsSmell alikemoderateCooked together5,991 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Onion + vinegartop 14% of all pairsSmell alikemoderateCooked together18,226 recipes
Shared aroma: acetic acid (sour, vinegar).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Cucumbers
- Provide the bulk of the sauce and its fresh, watery body once grated.
- Onions
- Add pungent flavour and aroma that mellows as the catsup stands.
- Vinegar
- Provides the acidity that preserves the sauce and gives it its sharp tang.
- Coarse sea salt
- Draws moisture out of the grated vegetables and seasons the sauce.
The step that matters
Letting the mixture stand. Salt and vinegar draw water out of the grated cucumber and onion and soften their raw bite over time. Stopping too early leaves the sauce thin and sharp; the standing period lets the flavours blend and the liquid develop.
Swap the onion
How well each one fits the dish's main ingredients (cucumber, vinegar, pepper):
- Capsicumfits better
- Radishfits better
- Mustardfits better
- Onionthe original
Fit is the average pairing score against cucumber, vinegar, 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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