Why it works: Horseradish and mustard 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
Chop the green tomatoes, onions, and green peppers finely.
Mix with coarse sea salt and let stand overnight.
Squeeze out all moisture using a cloth.
Season and pack
Add allspice, cloves, black pepper, horseradish, and white mustard seed; mix well.
Pack into a jar and cover with good 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.
-
Horseradish + mustardtop 1% of all pairsSmell alikestrongCooked together1,832 recipes
Shared aroma: coumarin (sweet, hay).
-
Allspice + clovetop 1% of all pairsSmell alikestrongCooked together7,874 recipes
Shared aroma: estragole (anise, licorice).
-
Allspice + mustardtop 2% of all pairsSmell alikestrongCooked together1,928 recipes
Shared aroma: methyleugenol (clove, spice).
-
Allspice + horseradishtop 4% of all pairsSmell alikestrongCooked together654 recipes
Shared aroma: coumarin (sweet, hay).
-
Pepper + clovetop 5% of all pairsSmell alikestrongCooked together17,451 recipes
Shared aroma: ethyl octanoate (fruity, wine).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Green tomatoes
- Provide the bulk of the relish and its firm, tart body.
- Onions
- Add savory sharpness and aroma that mellow during long salting.
- Coarse sea salt
- Draws moisture out of the chopped vegetables, firming them and concentrating flavor.
- White mustard seed
- Adds pungent heat and sharp flavor that softens in the vinegar.
- Good vinegar
- Acidity preserves the mixture and provides its tangy flavor.
The step that matters
Squeeze out all moisture using a cloth. Salt draws water out of the vegetables, but any moisture left behind dilutes the vinegar and can spoil the chow chow. Removing as much liquid as possible keeps the pickle firm and well preserved.
Swap the tomato
How well each one fits the dish's main ingredients (onion, pepper, allspice, clove, horseradish, mustard, vinegar):
- Shallotfits better
- Radishfits better
- Broccolifits better
- Tomatothe original
Fit is the average pairing score against onion, pepper, allspice, clove, horseradish, mustard, 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.
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