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
Prepare the tomatoes
If using fresh tomatoes, peel and slice them.
Place the tomatoes in a pot over medium heat and stew gently for about 30 minutes until tender.
Pass the cooked tomatoes through a sieve using a potato masher to create a puree.
Make the soup
Add ½ teaspoon of baking soda to the puree and enough milk to achieve the desired soup consistency.
Season with salt and pepper, then bring to a boil and serve.
For a thicker soup, add 1 quart of milk and thicken with finely powdered cracker dust, starting with 2 heaping tablespoons.
Alternatively, for thickening, melt 1 tablespoon of butter and 1 tablespoon of flour in a saucepan, then gradually add 1 pint of water.
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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Butter + flourtop 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).
Butter and flour 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 body and flavour of the soup once stewed and pureed.
- Baking soda
- Neutralises some of the tomato acidity, which keeps the milk from curdling.
- Milk
- Thins the puree and makes the soup creamy.
The step that matters
Adding baking soda to the puree. Baking soda reacts with the acidity of tomatoes and can cause milk to curdle if the soup is too acidic when milk is added. Mixing it in with the puree before adding milk helps keep the soup smooth.
Swap the tomato
How well each one fits the dish's main ingredients (milk, pepper, butter, flour):
- Potatofits better
- Capsicumfits better
- Chivefits better
- Tomatothe original
Fit is the average pairing score against milk, pepper, butter, flour. 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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