Why it works: Parsley and celery match in chemistry and in kitchens. They rank in the top 1% of all ingredient pairs, and cooks put them together in 6,810 recipes. Both carry 4'-methylacetophenone, which smells bitter almond. The science ↓
Tomato Soup
Ingredients
Directions
Make the soup
Boil the tomatoes in enough water to cover for 1 hour.
Strain the mixture through a colander.
Return the juice to the fire and add ½ cup milk thickened with a little flour.
Boil until slightly thickened, then slowly add 1 quart of milk after boiling.
Serve
Serve with dry toast and optional flavorings like parsley, onion, or celery.
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 their aromas overlap, and how often cooks already put them together.
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Parsley + celerytop 1% of all pairsSmell alikestrongCooked together6,810 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
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Tomato + celerytop 4% of all pairsSmell alikemoderateCooked together3,377 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
-
Onion + celerytop 7% of all pairsSmell alikemoderateCooked together18,518 recipes
Shared aroma: guaiacol (smoky, sweet).
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Tomato + oniontop 8% of all pairsSmell alikemoderateCooked together20,633 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Tomato + parsleytop 8% of all pairsSmell alikemoderateCooked together5,398 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
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 and flavor of the soup once boiled and strained.
- Milk
- Adds creaminess and richness to the soup base.
- Flour
- Thickens the milk so it gives the soup a smoother, heavier body.
The step that matters
Adding the milk slowly after boiling. Adding cold milk to a very hot acidic tomato base can cause it to curdle or separate. Adding it gradually and avoiding a hard boil afterward helps keep the soup smooth.
Swap the parsley
The recipe marks parsley as optional. How well each one fits the dish's main ingredients (tomato, milk, flour, onion, celery):
- Cuminfits better
- Turmericfits about as well
- Thymefits about as well
- Parsleythe original
Fit is the average pairing score against tomato, milk, flour, onion, celery. 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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