Name: Roast Duck
Ingredients: 1 duck; 1 small onion; 1 stalk of celery; coarse sea salt; black pepper; butter

Why it works: Celery and pepper match in chemistry and in kitchens. They rank in the top 5% of all ingredient pairs, and cooks put them together in 16,012 recipes. Both carry 4'-methylacetophenone, which smells bitter almond. The science ↓

Roast Duck

Ingredients

Directions

The book gives no oven temperature. The 350°F (175°C) in the steps was added when the recipe was transcribed, as a starting point. The book gives no cooking times either; the times in the steps were added in transcription, so check for doneness rather than trusting the clock.

Prepare

Preheat the oven to 350°F (175°C).
Truss the duck and season it inside and out with coarse sea salt and black pepper.
Place the small onion and stalk of celery inside the cavity of the duck.
Rub the outside of the duck with butter.

Roast and serve

Roast the duck in the oven for about 1.5 hours, basting occasionally.
Ensure the internal temperature reaches 165°F (74°C) before serving.

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.

Celery + peppertop 5% of all pairs

Smell alikestrong

Cooked together16,012 recipes

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

Smell alikemoderate

Cooked together18,518 recipes

Shared aroma: guaiacol (smoky, sweet).
Onion + peppertop 11% of all pairs

Smell alikemoderate

Cooked together68,474 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Onion + buttertop 15% of all pairs

Smell alikemoderate

Cooked together42,912 recipes

Shared aroma: decanal (soap, orange peel).
Pepper + buttertop 21% of all pairs

Smell alikemoderate

Cooked together85,593 recipes

Shared aroma: trans-2-nonenal (cardboard, fatty).

Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs

What each ingredient does

Duck: Provides the main protein and rich fat that bastes the meat as it roasts.
Butter: Adds fat and helps the outside skin brown and turn golden in the oven.

The step that matters

Ensure the internal temperature reaches 165°F (74°C) before serving. Duck can be served pink or undercooked if the thickest parts are not checked. Reaching a safe internal temperature confirms the meat is fully cooked, while a probe in the thickest part of the breast or thigh gives a reliable reading.