Why it works: Tomato and onion are a kitchen classic. They rank in the top 8% of all ingredient pairs, and 20,633 recipes mention both. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
Cream of Tomato Soup
Ingredients
Directions
Heat the tomatoes in a pot until boiling; cook until soft.
Press the tomatoes through a sieve and add baking soda.
Add boiling water to make 2 cups of stock.
Scald the milk with onion, spices, parsley, and bread crumbs; then press through a 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 + oniontop 8% of all pairsAroma overlapmoderateMentioned together20,633 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Tomato + parsleytop 8% of all pairsAroma overlapmoderateMentioned together5,398 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
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Onion + parsleytop 9% of all pairsAroma overlapmoderateMentioned together25,843 recipes
Shared aroma: 2,4-decadienal (seaweed).
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Tomato + breadtop 10% of all pairsAroma overlapmoderateMentioned together1,013 recipes
Shared aroma: 2-nonenal (fatty, green).
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Milk + breadtop 11% of all pairsAroma overlapmoderateMentioned together11,466 recipes
Shared aroma: 2-undecenal (sweet).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
Flavor stand-ins for the parsley
How well each one fits the dish's main ingredients (tomato, milk, onion, bread):
- Garlicbetter flavor fit
- Celerybetter flavor fit
- Thymebetter flavor fit
- Parsleythe original
Fit is the average pairing score against tomato, milk, onion, bread. Candidates are from the same food group and used in at least 100 recipes. This compares flavor only: it does not check the job the ingredient does in the dish (bulk, moisture, acidity, structure).
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