Name: Cucumber Catsup
Ingredients: 6 large cucumbers, peeled, grated, and drained; 3 green peppers, finely chopped; 2 onions, finely chopped; 2 tablespoons horseradish; 2 tablespoons coarse sea salt; ½ teaspoon black pepper; 1 quart vinegar

Why it works: Cucumber and horseradish match in chemistry and in kitchens. They rank in the top 2% of all ingredient pairs, and cooks put them together in 640 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓

Cucumber Catsup

Ingredients

6 large cucumbers, peeled, grated, and drained
3 green peppers, finely chopped
2 onions, finely chopped
2 tablespoons horseradish
2 tablespoons coarse sea salt
½ teaspoon black pepper
1 quart vinegar

Directions

Prepare

Grate and drain the cucumbers.
Finely chop the green peppers and onions.

Make the catsup

In a bowl, mix the grated cucumbers, chopped peppers, and onions.
Add horseradish, coarse sea salt, and black pepper.
Pour in the vinegar and stir well.

Recipe from a historical cookbook (Internet Archive).

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.

Cucumber + horseradishtop 2% of all pairs

Smell alikestrong

Cooked together640 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Onion + horseradishtop 7% of all pairs

Smell alikestrong

Cooked together1,784 recipes

Shared aroma: coumarin (sweet, hay).
Cucumber + oniontop 8% of all pairs

Smell alikestrong

Cooked together6,050 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Cucumber + vinegartop 8% of all pairs

Smell alikemoderate

Cooked together4,734 recipes

Shared aroma: 2-methylbutyl acetate (fruit).
Pepper + horseradishtop 11% of all pairs

Smell alikemoderate

Cooked together2,646 recipes

Shared aroma: coumarin (sweet, hay).

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 catsup, giving it its fresh, watery body.
Vinegar: Adds acidity that gives the catsup its sharp, tangy flavour and helps preserve it.
Onions: Add savoury depth and a sharp aromatic bite to the mixture.
Green peppers: Add a grassy, slightly bitter vegetable flavour and crisp texture.
Horseradish: Contributes a pungent heat that sharpens the overall flavour.

Swap the onion

How well each one fits the dish's main ingredients (cucumber, pepper, horseradish, vinegar):

Mustardfits better
Radishfits better
Cauliflowerfits better
Onionthe original

Fit is the average pairing score against cucumber, pepper, horseradish, 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.