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
Make the ketchup
Combine the skinned tomatoes, coarse sea salt, whole black pepper, allspice, red pepper, and mustard in a pot.
Boil the mixture for one hour.
Strain the mixture through a sieve or coarse cloth.
Bottle
Allow it to cool, then bottle it using the best velvet corks.
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).
-
Tomato + peppertop 7% of all pairsSmell alikemoderateCooked together17,923 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Pepper + mustardtop 9% of all pairsSmell alikemoderateCooked together15,430 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
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
- Skinned tomatoes
- Provide the main body, moisture and tomato flavour that the sauce is built on.
- Mustard
- Adds sharp, pungent flavour that balances the sweetness of the tomatoes.
- Red pepper
- Adds heat and a sharp, spicy note to the sauce.
The step that matters
Boiling the mixture for one hour. A long boil reduces the water in the tomatoes and concentrates their flavour and thickness. Boiling too briefly leaves the sauce thin and raw-tasting, while overcooking can dull the fresh tomato character.
Swap the tomato
How well each one fits the dish's main ingredients (pepper, allspice, mustard):
- Horseradishfits better
- Shallotfits better
- Broccolifits better
- Tomatothe original
Fit is the average pairing score against pepper, allspice, mustard. 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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