Why it works: Cucumber and mustard match in chemistry and in kitchens. They rank in the top 3% of all ingredient pairs, and cooks put them together in 2,281 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
Cucumber Catsup
Ingredients
Directions
Prepare
Peel and finely chop three dozen cucumbers and eighteen onions.
Sprinkle three-fourths pint table salt over them.
Put the whole in a sieve and let drain well overnight.
Season and cover
Add a tea-cup mustard seed and half tea-cup ground black pepper, and mix well.
Cover with good cider vinegar.
Nutrition, whole recipe (rough)
What these numbers assume: 5 portions
| Ingredient | Portion assumed | kcal |
|---|---|---|
| Cucumber | 1/2 cup sliced (52g) | 16 |
| Black Pepper | 1 tsp ground (2.3g) | 6 |
| Mustard | 1 tsp (5g) yellow | 3 |
| Vinegar | 1 tbsp (15ml) distilled | 3 |
| Salt | 1 tsp (6g) | 0 |
One typical portion per ingredient; the recipe's quantities are not counted. A rough guide only, not for medical or dietary planning.
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. See the original page.
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.
-
Cucumber + mustardtop 3% of all pairsSmell alikestrongCooked together2,281 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Mustard + vinegartop 7% of all pairsSmell alikemoderateCooked together14,067 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Cucumber + vinegartop 8% of all pairsSmell alikemoderateCooked together4,734 recipes
Shared aroma: 2-methylbutyl acetate (fruit).
-
Pepper + mustardtop 9% of all pairsSmell alikemoderateCooked together15,430 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Cucumber + peppertop 12% of all pairsSmell alikemoderateCooked together5,991 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
- Cucumbers
- Make up the bulk of the ketchup and give it its fresh, crisp base.
- Table salt
- Draws water out of the chopped vegetables, concentrating their flavour and firming their texture.
- Mustard seed
- Adds a sharp, pungent bite that balances the vinegar.
- Ground black pepper
- Contributes warm, sharp aroma and gentle heat.
- Cider vinegar
- Adds acidity that preserves the mixture and gives it its tang.
The step that matters
Draining overnight. Salt draws out a large amount of water from the cucumbers and onions. If they are not drained well, the ketchup will be thin and watery, and its flavour will be diluted.
Swap the cucumber
How well each one fits the dish's main ingredients (tea, pepper, mustard, vinegar):
- Lettucefits better
- Capsicumfits better
- Horseradishfits better
- Cucumberthe original
Fit is the average pairing score against tea, 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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