Name: Lemon Pickle or Catsup
Ingredients: 6 small lemons; 3 ounces coarse sea salt; 2½ ounces finely scraped horseradish; 2 ounces eschalots or 1½ ounces garlic; 1½ pints boiling vinegar; ½ ounce bruised ginger; ¼ ounce whole white pepper; 2 blades of mace

Why it works: Lemon and ginger match in chemistry and in kitchens. They rank in the top 5% of all ingredient pairs, and cooks put them together in 5,154 recipes. Both carry beta-phellandrene, which smells minty, terpene. The science ↓

Lemon Pickle or Catsup

Ingredients

Directions

Prepare the lemons

Divide the lemons into quarters and remove all visible seeds.
Sprinkle the salt over the lemons and let them sit for a week, turning occasionally.
After a week, place the lemons in a stone jar with their liquid.

Make the pickle

Add the horseradish, eschalots (or garlic), and pour the boiling vinegar over them.
Simmer the ginger, whole white pepper, and mace in the vinegar for 2-3 minutes before adding.
Let the pickle sit for 2-3 months before using, but it can be stored for 4-5 months before straining.

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.

Lemon + gingertop 5% of all pairs

Smell alikestrong

Cooked together5,154 recipes

Shared aroma: beta-phellandrene (minty, terpene).
Horseradish + garlictop 5% of all pairs

Smell alikestrong

Cooked together719 recipes

Shared aroma: coumarin (sweet, hay).
Garlic + gingertop 6% of all pairs

Smell alikemoderate

Cooked together6,402 recipes

Shared aroma: beta-phellandrene (minty, terpene).
Lemon + horseradishtop 9% of all pairs

Smell alikestrong

Cooked together1,155 recipes

Shared aroma: coumarin (sweet, hay).
Lemon + garlictop 9% of all pairs

Smell alikemoderate

Cooked together8,893 recipes

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

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

What each ingredient does

Lemons: Provide the sharp, fragrant citrus flesh and rind that form the pickle's base.
Coarse sea salt: Draws liquid out of the lemons and helps preserve them during the initial salting.
Horseradish: Adds pungent heat that mellows as the pickle matures.
Vinegar: Acidifies the pickle, preserving it and sharpening the flavour of the lemons.

Swap the mace

How well each one fits the dish's main ingredients (lemon, horseradish, garlic, vinegar, ginger, white pepper):

Turmericfits better
Dillfits better
Tarragonfits better
Macethe original

Fit is the average pairing score against lemon, horseradish, garlic, vinegar, ginger, white pepper. 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.