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
Make the soup
In a pot, heat the soup stock and season with salt and pepper.
Add the tomatoes and bring to a simmer.
Strain the mixture to remove solids.
Thicken and finish
In a small bowl, mix the flour with cold water until smooth.
Stir the flour mixture into the hot soup and cook until thickened.
If desired, add sugar to taste.
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 + sugartop 15% of all pairsAroma overlapmoderateMentioned together92,116 recipes
Shared aroma: phenylacetaldehyde (hawthorne, honey).
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Flour + peppertop 19% of all pairsAroma overlapmoderateMentioned together50,459 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Tomato + flourtop 22% of all pairsAroma overlapmoderateMentioned together7,065 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Sugar + peppertop 32% of all pairsAroma overlaplowMentioned together19,401 recipes
Shared aroma: 2-nonenal (fatty, green).
Sugar and pepper share little aroma chemistry, yet 19,401 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 flavor and body of the soup.
- Flour
- Thickens the soup as its starch swells in heat.
- Soup stock
- Forms the liquid base of the soup.
The step that matters
Stirring the flour mixture into the hot soup. Flour mixed with cold water must be smooth before it goes in, or it will clump. Stirring it into hot liquid lets the starch swell evenly, so the soup thickens without lumps.
“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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