Why it works: Onion and pepper are a kitchen classic. They rank in the top 11% of all ingredient pairs, and cooks put them together in 68,474 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
Cucumber Catsup
Ingredients
Directions
Prepare the cucumbers
Take green cucumbers, peel them, and let them lie in salt water for a short time.
If large, cut them in two and scrape out the seeds.
Grate the cucumbers on a coarse grater.
For every dozen cucumbers, grate one good-sized onion.
After all is grated, pour off the water that has collected.
Season and pack
Measure the water and, for as much water as you poured off, add the best cider vinegar.
Season with pepper and salt to taste.
If the vinegar is too sharp, dilute with cucumber water; if it is too thin, use less vinegar.
Put the mixture in jars like fruit; no heating required.
Nutrition, whole recipe (rough)
What these numbers assume: 4 portions
| Ingredient | Portion assumed | kcal |
|---|---|---|
| Onion | 1 medium (110g) | 44 |
| Black Pepper | 1 tsp ground (2.3g) | 6 |
| 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.
-
Onion + peppertop 11% of all pairsSmell alikemoderateCooked together68,474 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Onion + vinegartop 14% of all pairsSmell alikemoderateCooked together18,226 recipes
Shared aroma: acetic acid (sour, vinegar).
-
Vinegar + peppertop 14% of all pairsSmell alikemoderateCooked together27,814 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Cucumbers (in the method)
- Form the bulk of the relish and supply its crisp, fresh texture.
- Onion
- Adds sharp, aromatic flavour that balances the sweetness of the cucumber.
- Cider vinegar
- Provides acidity that preserves the relish and gives it its tang.
The step that matters
Pouring off the water and matching the vinegar to it. Grated cucumber releases a lot of water, and the vinegar is measured against that liquid. Adding too much vinegar makes the relish sharp and thin, so the balance depends on measuring the drained water first.
Swap the onion
How well each one fits the dish's main ingredients (vinegar, pepper):
- Capsicumfits better
- Mustardfits better
- Cabbagefits better
- Onionthe original
Fit is the average pairing score against 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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