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 ↓
Tomato Soup
Ingredients
Directions
Prepare
Cook the tomatoes until boiling, then add the baking soda.
Stir in the salt, pepper, and sugar.
Make the sauce
In a double boiler, heat the milk.
Cream the butter and flour together, thinning with a little hot milk.
Stir the butter and flour mixture into the milk and cook until thickened.
Finish and serve
Remove from heat and pour in the strained tomatoes.
Serve immediately.
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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Milk + buttertop 7% of all pairsAroma overlapmoderateMentioned together81,283 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
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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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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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Tomato + milktop 15% of all pairsAroma overlapmoderateMentioned together2,226 recipes
Shared aroma: 1-octen-3-one (mushroom, metallic).
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
- Tomatoes
- Provide the main body, acidity and tomato flavour of the soup.
- Milk
- Forms the creamy liquid base that gives the soup its smooth texture.
- Butter
- Adds richness and fat, carrying flavour and smoothing the texture.
- Flour
- Thickens the soup when cooked with butter and milk.
- Baking soda
- Neutralises the tomatoes' acidity, reducing the risk of the milk curdling.
The step that matters
Remove from heat and pour in the strained tomatoes.. Tomatoes are acidic, and acid can curdle hot milk. Removing the pan from the heat before adding them, after the baking soda has neutralised the acid, helps keep the soup smooth.
“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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