Why it works: Milk and butter are a kitchen classic. They rank in the top 7% of all ingredient pairs, and 81,283 recipes mention both. Both carry (z)-4-heptenal, which smells biscuit, cream. The science ↓
Cream of Tomato Soup
Ingredients
Directions
Make the soup
Put tomatoes, water, salt, pepper, sugar, parsley, and onion together, and cook 15 minutes.
Strain, put back on stove; when it comes to boil, add soda, milk, and butter, and flour creamed.
Serve
Serve with toast.
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. See the original page.
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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Milk + buttertop 7% of all pairsAroma overlapmoderateMentioned together81,283 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
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Onion + peppertop 11% of all pairsAroma overlapmoderateMentioned together68,474 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Butter + flourtop 12% of all pairsAroma overlaplowMentioned together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Milk + flourtop 14% of all pairsAroma overlaplowMentioned together78,219 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).
Butter and flour 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
- Milk
- Adds creaminess and a smooth, rich body to the soup.
- Butter
- Adds fat for richness and a silky mouthfeel.
- Flour
- Thickens the soup as it cooks with the butter and liquid.
- Sugar
- Adds sweetness that softens the tomato's acidity.
- Onion
- Adds savory aroma and depth to the tomato base.
The step that matters
Adding the milk to the hot tomato base. Tomatoes are acidic, and when hot acidic liquid meets milk it can curdle or separate. Keeping the heat moderate and the milk added gradually helps the soup stay smooth and creamy.
Flavor stand-ins for the onion
How well each one fits the dish's main ingredients (milk, butter, flour, sugar, pepper):
- Capsicumbetter flavor fit
- Potatobetter flavor fit
- Sweet potatobetter flavor fit
- Onionthe original
Fit is the average pairing score against milk, butter, flour, sugar, pepper. 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).
“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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