Name: Another Way to Pickle Walnuts
Ingredients: 100 walnuts; ½ cup mustard seed; ¼ ounce mace; ½ ounce black peppercorns; 6 bay leaves; good common vinegar; 1 onion; 30 cloves

Why it works: Mustard and onion match in chemistry and in kitchens. They rank in the top 6% of all ingredient pairs, and cooks put them together in 9,259 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓

Another Way to Pickle Walnuts

Ingredients

Directions

Prepare the walnuts

Gather the walnuts before the inner shell hardens; test with a pin.
Soak the walnuts in a mixture of salt and water for 9 days, changing the liquid every 3 days.
Remove the walnuts and dry them on a sieve or mat, ensuring they do not touch and are turned to blacken evenly.

Pickle and store

Place half the walnuts in a jar, add the onion with cloves, then add the remaining walnuts.
Boil the mustard seed, mace, black peppercorns, and bay leaves in vinegar.
Pour the boiling vinegar over the walnuts, ensuring they are fully covered.
Cover the jar with a cloth, then seal it with bladder or leather when cool.
After 6 weeks, check the walnuts; if any are dry, add more vinegar without boiling.

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.

Mustard + oniontop 6% of all pairs

Smell alikestrong

Cooked together9,259 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Mace + clovetop 6% of all pairs

Smell alikelow

Cooked together8,400 recipes

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

Smell alikemoderate

Cooked together14,067 recipes

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

Smell alikestrong

Cooked together3,829 recipes

Shared aroma: methyleugenol (clove, spice).
Walnut + mustardtop 9% of all pairs

Smell alikestrong

Cooked together849 recipes

Shared aroma: eucalyptol (eucalyptus, herbal).

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

What each ingredient does

Walnuts: Main ingredient that softens during salt soaking and takes on dark colour and pickled flavour.
Vinegar: Acidic liquid that preserves the walnuts and carries the pickling flavour.
Mustard seed: Adds sharp, pungent flavour to the pickling liquor.
Black peppercorns: Adds warm, sharp spice to the pickling liquor.
Onion: Adds savoury flavour to the pickle as it sits in the jar.

The step that matters

Drying the soaked walnuts. Walnuts must be spread so they do not touch and turned as they dry, so they blacken evenly. Uneven drying leaves pale patches and can let moisture trap spoilage in the jar.

Swap the mace

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

Allspicefits better
Tarragonfits better
Capersfits better
Macethe original

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

“What each ingredient does” and “The step that matters” were written by Claude from this recipe’s own method and reviewed in samples by CompKitchen.

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Another Way to Pickle Walnuts