Why it works: Milk and butter are a kitchen classic. They rank in the top 7% of all ingredient pairs, and cooks put them together in 81,283 recipes. Both carry (z)-4-heptenal, which smells biscuit, cream. The science ↓
Tomato Bisque Soup
Ingredients
Directions
Prepare
Stew the tomatoes in a pot.
Heat the milk in a double boiler, reserving ½ cup to mix with the flour.
Mix the flour smoothly with the reserved milk.
Stir the mixture into the boiling milk and cook for 10 minutes.
Make the soup
Add the baking soda to the stewed tomatoes and stir well.
Strain the mixture.
Combine the strained tomatoes with the milk, adding butter, salt, and pepper.
Serve
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 their aromas overlap, and how often cooks already put them together.
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Milk + buttertop 7% of all pairsSmell alikemoderateCooked together81,283 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
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Tomato + peppertop 7% of all pairsSmell alikemoderateCooked together17,923 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Flour + buttertop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Milk + flourtop 14% of all pairsSmell alikelowCooked together78,219 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Tomato + milktop 15% of all pairsSmell alikemoderateCooked together2,226 recipes
Shared aroma: 1-octen-3-one (mushroom, metallic).
Flour and butter barely smell alike, yet cooks put them together in 124,287 recipes: they 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, acidity and liquid body of the soup.
- Milk
- Forms the creamy base and makes up most of the soup's liquid.
- Flour
- Starch that thickens the milk into a smooth, body-rich base.
- Butter
- Adds fat for richer flavor and a silkier mouthfeel.
- Baking soda
- Neutralizes tomato acidity, which helps keep the milk from curdling.
The step that matters
Combining the tomatoes with the milk. Tomatoes are acidic, and acid can curdle hot milk. Adding baking soda to the stewed tomatoes first neutralizes much of that acid, and straining makes the mixture smooth before it meets the milk.
Swap the tomato
How well each one fits the dish's main ingredients (milk, flour, butter, pepper):
- Potatofits better
- Capsicumfits better
- Chivefits better
- Tomatothe original
Fit is the average pairing score against milk, flour, butter, pepper. 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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