Why it works: Horseradish and onion match in chemistry and in kitchens. They rank in the top 7% of all ingredient pairs, and cooks put them together in 1,784 recipes. Both carry coumarin, which smells sweet, hay. The science ↓
Pepper Sauce
Ingredients
Directions
Combine all ingredients in a kettle and boil until soft.
Rub the mixture through a sieve.
Season to taste with salt, spice, and a little sugar.
Boil again for 10 minutes.
Bottle and cork the sauce.
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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Horseradish + oniontop 7% of all pairsSmell alikestrongCooked together1,784 recipes
Shared aroma: coumarin (sweet, hay).
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Pepper + horseradishtop 11% of all pairsSmell alikemoderateCooked together2,646 recipes
Shared aroma: coumarin (sweet, hay).
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Pepper + oniontop 11% of all pairsSmell alikemoderateCooked together68,474 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Vinegar + horseradishtop 12% of all pairsSmell alikemoderateCooked together2,609 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Vinegar + oniontop 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
- Bell peppers
- Provide the main body and sweet, vegetal flavor of the sauce.
- Vinegar
- Adds acidity that sharpens flavor and helps keep the sauce stable.
- Onions
- Add savory depth and aroma as they soften during boiling.
- Horseradish
- Contributes sharp, pungent heat and aroma.
The step that matters
Rub the mixture through a sieve. Boiling until soft is not enough; pressing the cooked solids through a sieve breaks them down into a smooth, even sauce. Skipping or rushing this leaves a coarse, lumpy texture.
Swap the onion
How well each one fits the dish's main ingredients (pepper, vinegar, horseradish, sugar):
- Mustardfits better
- Beetrootfits better
- Radishfits better
- Onionthe original
Fit is the average pairing score against pepper, vinegar, horseradish, sugar. 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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