Name: Pickled Onions
Ingredients: onions; brine (saltwater solution); boiling vinegar; whole pepper; cloves

Why it works: Pepper and clove match in chemistry and in kitchens. They rank in the top 5% of all ingredient pairs, and cooks put them together in 17,451 recipes. Both carry ethyl octanoate, which smells fruity, wine. The science ↓

Pickled Onions

Ingredients

Directions

Peel the onions and place them in a brine that can float an egg for 48 hours.
Remove the onions from the brine and drain them.
Cover the onions with boiling hot vinegar.
Season with whole pepper and cloves.

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 + clovetop 5% of all pairs

Smell alikestrong

Cooked together17,451 recipes

Shared aroma: ethyl octanoate (fruity, wine).
Onion + peppertop 11% of all pairs

Smell alikemoderate

Cooked together68,474 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Onion + clovetop 13% of all pairs

Smell alikemoderate

Cooked together16,901 recipes

Shared aroma: 2-nonanone (fruity, floral).
Onion + vinegartop 14% of all pairs

Smell alikemoderate

Cooked together18,226 recipes

Shared aroma: acetic acid (sour, vinegar).
Vinegar + peppertop 14% of all pairs

Smell alikemoderate

Cooked together27,814 recipes

Shared aroma: 4'-methylacetophenone (bitter almond).