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 ↓
Potato Soup
Ingredients
Directions
Boil the diced potatoes in a little water for 20 minutes.
Add the milk, salt, and cayenne pepper, and boil slowly for another 20 minutes.
Mix the butter and flour together, then add to the soup and stir well.
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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Potato + peppertop 9% of all pairsSmell alikemoderateCooked together8,305 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Potato + milktop 9% of all pairsSmell alikemoderateCooked together3,611 recipes
Shared aroma: (e,z)-2,6-nonadienal (cucumber, melon).
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Butter + flourtop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Potato + buttertop 13% of all pairsSmell alikemoderateCooked together6,456 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
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
- Potatoes
- Provide starch and body that thickens the soup as they cook and break down.
- Milk
- Supplies the liquid base and richness, giving the soup a creamy texture.
- Butter and flour
- Form a roux-style paste that thickens the soup and adds richness when stirred in.
The step that matters
Adding the butter and flour mixture. If the flour is dropped in as lumps, it will not disperse and can cook into streaks. Mixing it fully with the butter first and stirring well into the hot soup helps it thicken evenly.
Swap the potato
How well each one fits the dish's main ingredients (milk, pepper, butter, flour):
- Potatothe original
- Capsicumfits about as well
- Chivefits less well
- Shallotfits less well
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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