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
Prepare the juice
Wash and boil the tomatoes until soft.
Pass the tomatoes through a colander, mashing until they stop dripping. You should have about 11 quarts of juice.
Cook
Put the juice in a china-lined kettle and add the salt, allspice, mustard, black pepper, and cayenne.
Boil for 2 hours; for a thicker catsup, boil for 3 to 4 hours.
Bottle and rest
Bottle the catsup, adding a little sweet oil on top to exclude air.
Seal the bottles and let them sit for 2 weeks before use.
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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Allspice + peppertop 5% of all pairsSmell alikestrongCooked together6,395 recipes
Shared aroma: estragole (anise, licorice).
-
Tomato + peppertop 7% of all pairsSmell alikemoderateCooked together17,923 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Mustard + peppertop 9% of all pairsSmell alikemoderateCooked together15,430 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Tomato + mustardtop 11% of all pairsSmell alikemoderateCooked together2,482 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 juice, which thickens and concentrates into the body of the catsup as it boils.
- Coarse sea salt
- Seasons the catsup and draws out moisture, helping preserve it during the long boil and rest.
- Ground mustard
- Adds sharp, pungent flavour that balances the sweetness of the reduced tomato.
- Allspice
- Contributes warm, aromatic spice notes that round out the tomato flavour.
- Cayenne
- Adds heat that builds gently into the background of the sauce.
The step that matters
Long, steady boil. Tomato juice thickens only as water evaporates, so boiling for the full time is what sets the body. Stopping early leaves a thin catsup that may spoil more readily, since concentration and salt both limit microbial growth.
Swap the tomato
How well each one fits the dish's main ingredients (allspice, mustard, pepper):
- Horseradishfits better
- Shallotfits better
- Broccolifits better
- Tomatothe original
Fit is the average pairing score against allspice, mustard, pepper. 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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