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
Strain the tomatoes and combine with boiling water.
Add baking soda, milk, butter, salt, and pepper.
Heat until scalding, but do not boil.
Stir in the rolled crackers and serve.
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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Butter + peppertop 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, flavor, and acidity of the soup.
- Baking soda
- Neutralizes some tomato acidity, which keeps the milk from curdling as easily.
- Milk
- Adds creaminess and mellows the tomato flavor into a smooth soup.
- Butter
- Adds richness and a silkier mouthfeel to the soup.
- Rolled crackers
- Thicken the soup slightly as they soak up liquid.
The step that matters
Heat until scalding, but do not boil. Once milk is added to the acidic tomato base, boiling can cause it to curdle or separate. Heating only to scalding keeps the soup smooth and creamy.
Swap the tomato
How well each one fits the dish's main ingredients (milk, butter, pepper):
- Potatofits better
- Capsicumfits better
- Tomatothe original
- Asparagusfits about as well
Fit is the average pairing score against milk, 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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