Name: Soup Stock. No. 2
Ingredients: bones and scraps from roast beef; any other bones or bits of veal, mutton, or chicken; bones from beef steak, veal, or lamb chops, cooked or raw; cold water; parsley; celery; onion

Why it works: Parsley and celery 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 ↓

Soup Stock. No. 2

Ingredients

Directions

After dinner, slice off nice cold roast beef.
Put the bones and scraps into a kettle and cover with cold water.
Add any other bones or bits of veal, mutton, or chicken.
Let cook slowly for 4 to 5 hours, then strain.
When cold, skim off all the fat.
Return to the kettle and heat, adding parsley, celery, or onion.
Use for soup or puree of peas or tomatoes.
Do not salt until after skimming, as salt will stop the scum from rising.

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.

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.

Parsley + celerytop 1% of all pairs

Smell alikestrong

Cooked together6,810 recipes

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

Smell alikemoderate

Cooked together17,092 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Celery + oniontop 7% of all pairs

Smell alikemoderate

Cooked together18,518 recipes

Shared aroma: guaiacol (smoky, sweet).
Parsley + oniontop 9% of all pairs

Smell alikemoderate

Cooked together25,843 recipes

Shared aroma: 2,4-decadienal (seaweed).
Beef + vealtop 11% of all pairs

Smell alikemoderate

Cooked together3,784 recipes

Shared aroma: 2,6-nonadienal (cucumber, green).