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 a dozen large ripe cucumbers.
Pare and cut them open, and take out all the seeds.
Grate the cucumbers.
Make a bag like a jelly-bag of some thin muslin cotton, and hang them up to drain overnight.
Make the catsup
Chop two or three onions and two or three green peppers.
Add a tablespoon of salt and the thin substance left in the bag, with a quart of best vinegar.
Nutrition, whole recipe (rough)
What these numbers assume: 3 portions
| Ingredient | Portion assumed | kcal |
|---|---|---|
| Onion | 1 medium (110g) | 44 |
| Pepper | 1 tsp ground (2.3g) | 6 |
| Vinegar | 1 tbsp (15ml) distilled | 3 |
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).
-
Vinegar + oniontop 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)
- Make up the main body of the sauce, and their liquid is drained away to leave a thicker texture.
- Onions
- Add pungent, savoury flavour that deepens as the sauce sits.
- Green peppers
- Add a fresh, slightly bitter vegetable flavour to the sauce.
- Vinegar
- Adds sharp acidity that brightens flavour and helps preserve the sauce.
The step that matters
Draining the grated cucumbers overnight. Cucumbers are mostly water. If they are not drained well, the excess liquid thins the catsup and dilutes its flavour, so the bag should hang long enough to release as much liquid as possible.
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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