Why it works: Tomato and pepper are a kitchen classic. They rank in the top 7% of all ingredient pairs, and 17,923 recipes mention both. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
Tomato Soup
Ingredients
Directions
In a pot, bring 1 pint of water to a boil.
Add 1 can of tomatoes and bring to a boil again.
Mix 2 tablespoons of flour with some juice from the pot.
Add the flour mixture to the pot along with sugar, salt, butter, and pepper to taste.
Boil for 20 minutes, then strain through a fine sieve.
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.
Photo for illustrative purposes only · Contact us to use it
Explore the science
The flavor team
The pairs that carry this dish. Each one is judged two ways: how much aroma chemistry they share, and how many recipes mention both.
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Tomato + peppertop 7% of all pairsAroma overlapmoderateMentioned together17,923 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Flour + buttertop 12% of all pairsAroma overlaplowMentioned together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Flour + sugartop 15% of all pairsAroma overlapmoderateMentioned together92,116 recipes
Shared aroma: phenylacetaldehyde (hawthorne, honey).
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Sugar + buttertop 17% of all pairsAroma overlapmoderateMentioned together98,233 recipes
Shared aroma: guaiacol (smoky, sweet).
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Flour + peppertop 19% of all pairsAroma overlapmoderateMentioned together50,459 recipes
Shared aroma: isobutyraldehyde (malty, green).
Flour and butter share little aroma chemistry, yet 124,287 recipes mention both: they likely work on texture and structure more than aroma.
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, acidity and flavor of the soup.
- Flour
- Thickens the soup by swelling in the hot liquid, giving it body.
The step that matters
Mixing the flour with pot juice before adding it. Raw flour added directly to hot liquid clumps into lumps that are hard to smooth out. Mixing it first with some liquid disperses the starch so it thickens the soup evenly.
“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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