Why it works: Allspice and mustard match in chemistry and in kitchens. They rank in the top 2% of all ingredient pairs, and cooks put them together in 1,928 recipes. Both carry methyleugenol, which smells clove, spice. The science ↓
Tomato Catsup
Ingredients
Directions
Bruise the tomatoes, salt, black pepper, allspice, red pepper pods, and mustard seed finely.
Simmer the mixture slowly in 1 pint of vinegar for 3 hours.
Strain the mixture and boil it down to 2 quarts.
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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Allspice + mustardtop 2% of all pairsSmell alikestrongCooked together1,928 recipes
Shared aroma: methyleugenol (clove, spice).
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Pepper + allspicetop 5% of all pairsSmell alikestrongCooked together6,395 recipes
Shared aroma: estragole (anise, licorice).
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Tomato + peppertop 7% of all pairsSmell alikemoderateCooked together17,923 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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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
- Tomatoes
- Provide the bulk of the sauce and its body and flavor once simmered and reduced.
- Vinegar
- Adds acidity that gives the ketchup its tang and helps preserve it.
- Mustard seed
- Contributes a sharp, pungent aroma and a slight bite to the sauce.
- Red pepper pods
- Add heat and a pungent, spicy note to the finished sauce.
The step that matters
Boil it down to 2 quarts. Reducing the strained mixture concentrates flavor and thickens the sauce. Stopping too early leaves it thin and watery, while over-reducing makes it overly dense and can scorch on the bottom of the pan.
Swap the tomato
How well each one fits the dish's main ingredients (pepper, allspice, mustard, vinegar):
- Horseradishfits better
- Radishfits better
- Shallotfits better
- Tomatothe original
Fit is the average pairing score against pepper, allspice, 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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