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
Wash and chop the tomatoes, then combine them in a large pot with vinegar, allspice, cloves, black pepper, onions or garlic, salt, and red peppers.
Boil the mixture for a long time, stirring occasionally.
Strain the mixture through a sieve to remove solids.
Add the vinegar last and continue to boil until the catsup thickens.
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).
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Allspice + peppertop 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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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, flavor, and bulk that the sauce cooks down into.
- Vinegar
- Adds acidity that sharpens flavor and helps preserve the finished sauce.
- Onions or garlic
- Add savory aromatic depth to the sauce.
- Red peppers
- Contribute sweetness and color along with a fresh vegetable flavor.
- Salt
- Seasons the sauce and draws out moisture from the vegetables.
The step that matters
Boil until the catsup thickens. Long simmering evaporates water from the tomato mixture, concentrating flavor and thickening the sauce. Stopping too early leaves it thin, while the vinegar is added last so its sharp acidity is not boiled off during the long cook.
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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