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 the pulp
Pare, seed, and grate the cucumbers.
Let the pulp drain overnight in a thin bag.
Discard the juice and add the salt and vinegar to the pulp.
Make the catsup
Stir in the finely chopped onions and peppers.
Mix well and seal in bottles.
Serve with fish.
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 pulp, which gives the catsup its body once drained.
- Onions
- Add pungent flavour and aroma that balance the sharpness of the vinegar.
- Red peppers
- Add sweetness and colour along with a mild, fresh bite.
- Vinegar
- Adds acidity that sharpens the flavour and helps preserve the catsup in bottles.
The step that matters
Draining the pulp overnight. Cucumbers hold a lot of water. If the juice is not drained off and discarded, the catsup will be thin and watery, and the salt and vinegar will be diluted, weakening both texture and keeping quality.
Swap the onion
How well each one fits the dish's main ingredients (cucumber, pepper, vinegar):
- Capsicumfits better
- Radishfits better
- Mustardfits better
- Onionthe original
Fit is the average pairing score against cucumber, pepper, 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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