Why it works: Cider and vinegar are a kitchen classic. They rank in the top 6% of all ingredient pairs, and cooks put them together in 3,431 recipes. Both carry 4-ethyl-2-methoxyphenol, which smells smoky, clove. The science ↓
Tomato Catsup
Ingredients
Directions
In a large pot, combine the strained cooked tomatoes and cider vinegar.
Add salt, mustard, black pepper, red pepper, and adjust with spice and sugar to taste.
Boil the mixture for two hours, stirring occasionally.
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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Cider + vinegartop 6% of all pairsSmell alikemoderateCooked together3,431 recipes
Shared aroma: 4-ethyl-2-methoxyphenol (smoky, clove).
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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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Vinegar + mustardtop 7% of all pairsSmell alikemoderateCooked together14,067 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Mustard + peppertop 9% of all pairsSmell alikemoderateCooked together15,430 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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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
- Strained cooked tomatoes
- Form the bulk of the sauce and supply its body and tomato flavor.
- Cider vinegar
- Adds acidity that gives the ketchup its tang and helps preserve it.
- Mustard
- Contributes sharp, pungent flavor that balances the sweetness and acidity.
- Salt
- Seasons the sauce and sharpens the tomato flavor.
The step that matters
Boil the mixture for two hours, stirring occasionally. Long simmering evaporates water and concentrates the tomatoes into a thick sauce. Stirring prevents scorching on the bottom of the pot, which would add a burnt flavor.
Swap the tomato
How well each one fits the dish's main ingredients (cider, vinegar, mustard, pepper, sugar):
- Horseradishfits better
- Capsicumfits better
- Radishfits better
- Tomatothe original
Fit is the average pairing score against cider, vinegar, mustard, pepper, sugar. 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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