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
Prepare
Wash the tomatoes.
Chop the tomatoes.
Place the tomatoes in a large pot.
Make the ketchup
Add the vinegar, allspice, cloves, black pepper, onions or garlic, salt, and red peppers to the pot.
Boil the mixture for a long time, stirring occasionally.
Strain the mixture through a sieve to remove solids.
Return the strained liquid to the pot.
Boil until thickened.
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).
-
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
- Form the bulk of the sauce and provide its base flavor, color and body.
- Vinegar
- Adds acidity that sharpens flavor and helps preserve the finished ketchup.
- Onions or garlic
- Add savory depth and aroma to the sauce.
- Red peppers
- Contribute sweetness, color and a mild pepper flavor.
- Salt
- Seasons the sauce and draws out flavor from the vegetables.
The step that matters
Boil until thickened. Long simmering evaporates water so the sauce reduces and sets to a thick consistency. Stopping early leaves it thin and watery, and scorching can occur if it is left unstirred near the end.
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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