Name: Walnut Pickle
Ingredients: White walnuts or English walnuts or black walnuts; Boiling water; Coarse sea salt; Vinegar; Black pepper; Cloves; Garlic; Mustard seed; Mace

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 ↓

Walnut Pickle

Ingredients

Directions

Gather walnuts in early June while the outer rind is soft.
Place them in a jar and cover with boiling saltwater strong enough to float an egg.
Let them sit for nine days, changing the brine every three days.
Spread the walnuts on a dish to dry in the air, turning them at least once.
Soak the walnuts in fresh water overnight.
The next day, place them in a kettle and cover with vinegar and spices.
Bring to a boil, then pour off the vinegar and boil it alone for three days, scalding the pickles each time.
Once cooled, seal the pickles tightly.

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).
Garlic + mustardtop 6% of all pairs

Smell alikestrong

Cooked together4,053 recipes

Shared aroma: linalool (floral, citrus).
Clove + macetop 6% of all pairs

Smell alikelow

Cooked together8,400 recipes

Shared aroma: methyleugenol (clove, spice).
Vinegar + mustardtop 7% of all pairs

Smell alikemoderate

Cooked together14,067 recipes

Shared aroma: isobutyraldehyde (malty, green).
Pepper + garlictop 8% of all pairs

Smell alikemoderate

Cooked together27,090 recipes

Shared aroma: beta-phellandrene (minty, terpene).

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

Swap the mace

How well each one fits the dish's main ingredients (walnut, vinegar, pepper, clove, garlic, mustard):

Tarragonfits better
Allspicefits better
Thymefits better
Macethe original

Fit is the average pairing score against walnut, vinegar, pepper, clove, garlic, mustard. Candidates are from the same food group and used in at least 100 recipes.