Name: The Haggis
Ingredients: 1 pound finely-shred suet; 2 chopped onions; ½ pint oatmeal (or ½ pound oat-cakes, toasted and crumbled); 2 teaspoons coarse sea salt; 1 teaspoon black pepper; ½ nutmeg, grated; a pinch of cayenne; ½ pint good gravy; juice of 1 small lemon

Why it works: Pepper and lemon match in chemistry and in kitchens. They rank in the top 3% of all ingredient pairs, and cooks put them together in 27,047 recipes. Both carry trans-2-nonenal, which smells cardboard, fatty. The science ↓

The Haggis

Ingredients

Directions

Boil the pluck for 30 minutes in water, then transfer to fresh water.
Boil the pluck for an additional 30 minutes.
Trim away skins and discolored parts from the pluck.
Grate half of the liver and mince the rest finely.
Combine the liver, suet, onions, oatmeal (or oat-cakes), salt, pepper, nutmeg, and cayenne in a bowl.
Moisten the mixture with gravy and lemon juice.
Place the mixture into a prepared bag, leaving room for swelling, and sew it securely.
Plunge the bag into boiling water and boil gently for 3 hours.
Prick the bag with a needle occasionally, especially in the first half hour, to release air.
Serve hot without sauce or gravy.

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.

Pepper + lemontop 3% of all pairs

Smell alikestrong

Cooked together27,047 recipes

Shared aroma: trans-2-nonenal (cardboard, fatty).
Nutmeg + lemontop 5% of all pairs

Smell alikestrong

Cooked together11,318 recipes

Shared aroma: beta-phellandrene (minty, terpene).
Pepper + nutmegtop 7% of all pairs

Smell alikestrong

Cooked together13,015 recipes

Shared aroma: 4'-methylacetophenone (bitter almond).
Onion + peppertop 11% of all pairs

Smell alikemoderate

Cooked together68,474 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Onion + nutmegtop 16% of all pairs

Smell alikemoderate

Cooked together5,371 recipes

Shared aroma: acetic acid (sour, vinegar).