Why it works: Allspice and clove match in chemistry and in kitchens. They rank in the top 1% of all ingredient pairs, and cooks put them together in 7,874 recipes. Both carry estragole, which smells anise, licorice. The science ↓
Tomato Catsup
Ingredients
Directions
Make the base
Wash and chop the tomatoes, then combine them with vinegar, allspice, cloves, black pepper, onions (or garlic), salt, and red peppers in a large pot.
Cook and finish
Boil the mixture for a long time until it thickens.
Strain the mixture through a sieve.
Add the vinegar last and boil again until thick enough.
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 + clovetop 1% of all pairsSmell alikestrongCooked together7,874 recipes
Shared aroma: estragole (anise, licorice).
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Clove + peppertop 5% of all pairsSmell alikestrongCooked together17,451 recipes
Shared aroma: ethyl octanoate (fruity, wine).
-
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).
-
Tomato + oniontop 8% of all pairsSmell alikemoderateCooked together20,633 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 main body, bulk, and fruity flavor of the ketchup.
- Vinegar
- Adds sharp acidity that balances the sweetness of the tomatoes and peppers.
- Onions or garlic
- Contribute savory depth and aroma to the sauce.
- Red peppers
- Add sweetness and mild, rounded pepper flavor to the sauce.
- Allspice
- Adds warm, aromatic spice notes that define the ketchup's flavor.
- Cloves
- Contribute strong, warm aroma that carries through the long cooking.
The step that matters
Boil until thick. Long boiling evaporates water and concentrates the tomato pulp into a thick sauce. Stir often near the end, because the thickened mixture can scorch or stick to the base of the pot.
Swap the onion
How well each one fits the dish's main ingredients (tomato, vinegar, allspice, clove, pepper):
- Capsicumfits better
- Mustardfits better
- Carrotfits better
- Onionthe original
Fit is the average pairing score against tomato, vinegar, allspice, clove, 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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