Name: Mushroom Catsup
Ingredients: large fresh mushrooms (known as umbrellas or flaps); coarse sea salt; black pepper; allspice; cloves; peppercorns

Why it works: Allspice and clove match in chemistry and in kitchens. They rank in the top 1% of all ingredient pairs, and cooks put them together in 7,874 recipes. Both carry estragole, which smells anise, licorice. The science ↓

Mushroom Catsup

Ingredients

Directions

Wash and cut the mushrooms into two or four pieces.
Layer the mushrooms in a wide, flat jar or crock, sprinkling each layer with coarse sea salt.
Let them stand for 24 hours.
Press out the juice and bottle it, then return the mushrooms to the jar.
After another 24 hours, press the mushrooms again and bottle the juice.
Repeat this process one more time.
Combine all the extracted juice in a pot, add black pepper, allspice, and pounded cloves.
Boil the mixture and skim off any scum that rises.
Once cool, bottle the catsup, adding two cloves and a peppercorn to each bottle.
Cork and seal the bottles, then store them in a dry place.

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.

Allspice + clovetop 1% of all pairs

Smell alikestrong

Cooked together7,874 recipes

Shared aroma: estragole (anise, licorice).
Pepper + clovetop 5% of all pairs

Smell alikestrong

Cooked together17,451 recipes

Shared aroma: ethyl octanoate (fruity, wine).
Pepper + allspicetop 5% of all pairs

Smell alikestrong

Cooked together6,395 recipes

Shared aroma: estragole (anise, licorice).
Mushroom + clovetop 10% of all pairs

Smell alikemoderate

Cooked together2,663 recipes

Shared aroma: alpha-pinene (pine, turpentine).
Mushroom + peppertop 11% of all pairs

Smell alikemoderate

Cooked together13,580 recipes

Shared aroma: 2-nonenal (fatty, green).