Why it works: Pepper and clove match in chemistry and in kitchens. They rank in the top 5% of all ingredient pairs, and cooks put them together in 17,451 recipes. Both carry ethyl octanoate, which smells fruity, wine. The science ↓
Tomato Catsup
Ingredients
Directions
Make the tomato base
Stew the tomatoes with salt until soft.
Pass through a colander and cook until thick.
Optionally, add chopped onions at the beginning.
Season and finish
Add sugar, Cayenne, black pepper, ground cloves, mustard, and vinegar.
Stir while cooking to prevent sticking.
Pass through a sieve to remove seeds.
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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Pepper + clovetop 5% of all pairsSmell alikestrongCooked together17,451 recipes
Shared aroma: ethyl octanoate (fruity, wine).
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Mustard + oniontop 6% of all pairsSmell alikestrongCooked together9,259 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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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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Mustard + vinegartop 7% of all pairsSmell alikemoderateCooked together14,067 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Clove + mustardtop 8% of all pairsSmell alikestrongCooked together3,829 recipes
Shared aroma: methyleugenol (clove, spice).
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 body and flavour when stewed down.
- Sugar
- Adds sweetness that balances the acidity of the vinegar and tomatoes.
- Vinegar
- Adds acidity that gives ketchup its tang and helps preserve it.
- Onions
- Add savoury depth and aroma to the sauce when included.
The step that matters
Stir while cooking. Tomato sauce is thick and sugar-rich, so it scorches easily on the bottom of the pan. Constant stirring keeps it from sticking and burning, which would give a bitter taste.
Swap the onion
The recipe marks onion as optional. How well each one fits the dish's main ingredients (tomato, sugar, pepper, clove, mustard, vinegar):
- Capsicumfits better
- Horseradishfits better
- Lettucefits better
- Onionthe original
Fit is the average pairing score against tomato, sugar, pepper, clove, mustard, vinegar. 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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