Name: To Pickle Onions
Ingredients: white onions; boiling water; coarse sea salt; plain cold vinegar; turmeric

Why it works: Onion and turmeric are a kitchen classic. They rank in the top 8% of all ingredient pairs, and cooks put them together in 6,913 recipes. Both carry guaiacol, which smells smoky, sweet. The science ↓

To Pickle Onions

Ingredients

Directions

Select small white onions and cut the stem close to the root.
Place the onions in a pot and cover them with boiling water and coarse sea salt.
Seal the pot and let it sit for two weeks, changing the salt and water every three days.
Stir the onions daily to prevent floating ones from becoming soft.
After two weeks, remove the skin and outer shell from the onions.
Submerge the onions in plain cold vinegar with a little turmeric.

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.

Onion + turmerictop 8% of all pairs

Smell alikemoderate

Cooked together6,913 recipes

Shared aroma: guaiacol (smoky, sweet).
Onion + vinegartop 14% of all pairs

Smell alikemoderate

Cooked together18,226 recipes

Shared aroma: acetic acid (sour, vinegar).
Vinegar + turmerictop 19% of all pairs

Smell alikemoderate

Cooked together2,214 recipes

Shared aroma: isobutyraldehyde (malty, green).