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 ↓
Green Pea Soup
Ingredients
Directions
Make the white sauce
Scald the milk in a double boiler.
Melt the butter, then stir in the flour, salt, and pepper until smooth.
Stir the mixture into the scalded milk and cook for 10 minutes, stirring until smooth.
Add the peas
Heat the peas in their own liquid, then mash through a strainer.
Add the pea pulp to the milk mixture 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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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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Peas + peppertop 15% of all pairsSmell alikemoderateCooked together5,331 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Milk + peastop 16% of all pairsSmell alikemoderateCooked together1,309 recipes
Shared aroma: hexanal (green, grassy).
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
- Milk
- Forms the liquid base of the soup and, with the flour and butter, a smooth thickened body.
- Butter
- Enriches the sauce with fat and carries flavour, and helps form the roux with the flour.
- Flour
- Thickens the milk when cooked with butter, giving the soup a smooth, body-rich texture.
- Peas
- Provide the main flavour and colour, and their pulp adds body to the soup.
The step that matters
Stir the mixture into the scalded milk and cook until smooth. Flour thickens only when its starch gelatinises in hot liquid. Adding the roux to milk while stirring constantly keeps lumps from forming, and the full cooking time lets the starch swell and thicken the sauce evenly.
Swap the peas
How well each one fits the dish's main ingredients (milk, butter, flour, pepper):
- Almondfits better
- Chestnutfits better
- Milletfits better
- Peasthe original
Fit is the average pairing score against milk, butter, flour, 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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