Why it works: Onion and pepper are a kitchen classic. They rank in the top 11% of all ingredient pairs, and cooks put them together in 68,474 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
Swiss Potato Soup
Ingredients
Directions
Drain the potatoes and add the sliced onion and boiling water.
Cook until the vegetables are soft, then drain, reserving the water.
Rub the vegetables through a sieve and add the reserved water back.
Reheat the mixture and bind it with shortening and flour cooked together.
Season with coarse sea salt and pepper.
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.
-
Onion + peppertop 11% of all pairsSmell alikemoderateCooked together68,474 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Milk + flourtop 14% of all pairsSmell alikelowCooked together78,219 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Onion + flourtop 17% of all pairsSmell alikemoderateCooked together32,460 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Flour + peppertop 19% of all pairsSmell alikemoderateCooked together50,459 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Onion + milktop 20% of all pairsSmell alikemoderateCooked together13,418 recipes
Shared aroma: hexanal (green, grassy).
Milk and flour barely smell alike, yet cooks put them together in 78,219 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
Swap the onion
How well each one fits the dish's main ingredients (milk, flour, pepper):
- Capsicumfits better
- Arrowrootfits better
- Potatofits better
- Onionthe original
Fit is the average pairing score against milk, flour, pepper. Candidates are from the same food group and used in at least 100 recipes.
You might also like
Tomato Soup526 recipes
Brown Bread461 recipes
Mutton Broth292 recipes
Yorkshire Pudding264 recipesThe free Flavor Lab newsletter: one surprising pairing a week and the molecular reason it works, in 60 seconds. No spam, unsubscribe anytime.
Prefer an account? Create a free account to save pairings and unlock the full chemistry.