Why it works: Mustard and horseradish match in chemistry and in kitchens. They rank in the top 1% of all ingredient pairs, and cooks put them together in 1,832 recipes. Both carry coumarin, which smells sweet, hay. The science ↓
Chow Chow
Ingredients
Directions
Prepare
Layer the chopped peppers and onions in a bowl, sprinkling each layer with salt.
Let the mixture stand overnight.
In the morning, drain the mixture.
Pack and seal
Add the white mustard seed and horseradish, if using, and mix well.
Pack the mixture into sterilized jars, filling them to the top with scalded vinegar.
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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Mustard + horseradishtop 1% of all pairsSmell alikestrongCooked together1,832 recipes
Shared aroma: coumarin (sweet, hay).
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Onion + mustardtop 6% of all pairsSmell alikestrongCooked together9,259 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Onion + horseradishtop 7% of all pairsSmell alikestrongCooked together1,784 recipes
Shared aroma: coumarin (sweet, hay).
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Mustard + vinegartop 7% of all pairsSmell alikemoderateCooked together14,067 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Pepper + mustardtop 9% of all pairsSmell alikemoderateCooked together15,430 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
- Peppers
- Provide the main bulk and mild crunch, releasing moisture that salt draws out during standing.
- Onions
- Add savory sharpness and bulk, softening slightly as they stand in salt.
- White mustard seed
- Adds pungent, sharp flavor that mellows during storage in vinegar.
- Horseradish
- Adds sharp, pungent heat that gives the relish its bite.
The step that matters
Draining after the overnight salt rest. Salt draws water out of the vegetables by osmosis. Draining removes that liquid so the relish stays crisp and does not dilute the vinegar in the jars.
“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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