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 Soup
Ingredients
Directions
Make the soup base
Bring 1 quart of water to a boil in a pot.
Add 1 quart of canned tomatoes or 8 large tomatoes and cook until very tender.
Stir in 1 teaspoon of baking soda and wait for the foaming to stop.
Once the foaming stops, add 1 quart of cold milk and season with pepper, salt, and butter.
Bring the mixture to a boil.
Finish and serve
Crush a few crackers finely and add them just before removing the soup from the heat.
Butter whole crackers and place them at the bottom of a tureen.
Pour the soup over the buttered crackers.
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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Tomato + milktop 15% of all pairsSmell alikemoderateCooked together2,226 recipes
Shared aroma: 1-octen-3-one (mushroom, metallic).
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Pepper + buttertop 21% of all pairsSmell alikemoderateCooked together85,593 recipes
Shared aroma: trans-2-nonenal (cardboard, fatty).
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Tomato + buttertop 22% of all pairsSmell alikemoderateCooked together6,918 recipes
Shared aroma: 3-hexenal (apple, fruity).
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 flavour of the soup as they cook down until very tender.
- Baking soda
- Neutralises the tomatoes' acidity, which makes the milk less likely to curdle and causes foaming.
- Milk
- Adds creaminess and mild sweetness, turning the tomato base into a smooth, rich soup.
- Crackers
- Thicken the soup slightly and add body, both crushed into it and laid whole in the tureen.
The step that matters
Adding the baking soda before the milk. Baking soda reacts with the tomato acid and foams vigorously, so the foaming must settle before the milk goes in. Adding milk too early can cause curdling and an uneven texture.
Swap the tomato
How well each one fits the dish's main ingredients (milk, pepper, butter):
- Potatofits better
- Capsicumfits better
- Tomatothe original
- Asparagusfits about as well
Fit is the average pairing score against milk, pepper, butter. 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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