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 the tomatoes
Stew the tomatoes in a pot.
Add the baking soda to the stewed tomatoes.
Stir the tomatoes well.
Strain the tomato mixture.
Make the milk base
Heat the milk in a double boiler.
Reserve ½ cup of the milk for the flour mixture.
Mix the flour with the reserved milk until smooth.
Stir the flour mixture into the boiling milk.
Cook the mixture for 10 minutes.
Add the butter, salt, and pepper to the milk mixture.
Combine and serve
Add the strained tomatoes to the milk mixture.
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 and body of the bisque.
- Milk
- Forms the creamy, smooth base of the soup.
- Flour
- Thickens the milk so the bisque becomes smooth and velvety.
- Butter
- Adds richness and a silky mouthfeel to the soup.
- Baking soda
- Neutralizes some tomato acidity, reducing sharpness and curdling risk.
The step that matters
Adding the strained tomatoes to the milk mixture. Acidic tomatoes can curdle hot milk, causing the bisque to separate. Adding the baking soda to the tomatoes first lowers their acidity, and keeping the milk mixture hot but not boiling helps it stay smooth.
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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