Name: Potato Soup
Ingredients: 1 quart milk; ⅛ teaspoon pepper; 2 slices onion; ⅛ teaspoon celery salt; 3 tablespoons butter; a few grains cayenne pepper; 2 tablespoons flour; 1 teaspoon chopped parsley

Why it works: Celery and parsley match in chemistry and in kitchens. They rank in the top 1% of all ingredient pairs, and cooks put them together in 6,810 recipes. Both carry 4'-methylacetophenone, which smells bitter almond. The science ↓

Potato Soup

Ingredients

Directions

Cook potatoes in boiling salted water until soft, then rub through a strainer.
Scald milk with onion, then remove the onion.
Slowly add the milk to the potatoes.
Melt half the butter, add the dry ingredients, and stir until well mixed.
Stir the mixture into the boiling soup and cook for 1 minute.
Strain the soup, add the remaining butter, and sprinkle with parsley.

Recipe from a historical cookbook (Internet Archive).

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.

Celery + parsleytop 1% of all pairs

Smell alikestrong

Cooked together6,810 recipes

Shared aroma: 4'-methylacetophenone (bitter almond).
Pepper + parsleytop 2% of all pairs

Smell alikestrong

Cooked together34,122 recipes

Shared aroma: 4'-methylacetophenone (bitter almond).
Pepper + celerytop 5% of all pairs

Smell alikestrong

Cooked together16,012 recipes

Shared aroma: 4'-methylacetophenone (bitter almond).
Milk + buttertop 7% of all pairs

Smell alikemoderate

Cooked together81,283 recipes

Shared aroma: (z)-4-heptenal (biscuit, cream).
Onion + celerytop 7% of all pairs

Smell alikemoderate

Cooked together18,518 recipes

Shared aroma: guaiacol (smoky, sweet).

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, pepper, celery, butter, flour, parsley):

Carrotfits better
Potatofits better
Parsnipfits better
Onionthe original

Fit is the average pairing score against milk, pepper, celery, butter, flour, parsley. Candidates are from the same food group and used in at least 100 recipes.