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
Cook the tomatoes
Cook the tomatoes in the water until soft.
Add a small pinch of baking soda.
Add the milk and season
Heat the milk and mix it with the tomato mixture.
Season with butter, pepper, and coarse sea salt to taste.
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
- Form the soup's main body and provide its bright, slightly acidic flavour.
- Baking soda
- Neutralises some of the tomatoes' acidity, making the soup taste less sharp.
- Milk
- Adds creaminess and softens the tomato flavour.
- Butter
- Adds fat for richer flavour and a smoother mouthfeel.
The step that matters
Mixing the hot milk into the tomatoes. Tomatoes are acidic, and acid combined with the milk proteins can make the milk curdle, especially when it is very hot. Heating the milk gently and adding it slowly while stirring helps keep the soup smooth. The baking soda raises the acidity balance, which also helps protect against curdling.
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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