Skip to main content
Main

Lemon Ketchup for Fish

A citrusy condiment made by boiling spices, horseradish, lemon rind, and salt with lemon juice.

From an old cookbook · modernised transcription
From a historical cookbook (Internet Archive) · 9 ingredients
Jump to recipe ↓

Why it works: Mustard and horseradish match in chemistry and in kitchens. They rank in the top 1% of all ingredient pairs, and cooks put them together in 1,832 recipes. Both carry coumarin, which smells sweet, hay. The science ↓

Lemon Ketchup for Fish

Ingredients

Directions

Prepare the spice mix

  1. Pound the mace, mustard seed, celery seed, cloves, and black pepper very fine.

  2. Mix the spices with the grated horseradish and grated lemon rind.

  3. Add the coarse sea salt and moisten with lemon juice.

Cook and age

  1. Boil the mixture for 30 minutes.

  2. Pour into a bottle, cork it tightly, and let it stand for one month.

Finish and seal

  1. After a month, strain the mixture and seal the bottles.

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.

  1. Mustard + horseradishtop 1% of all pairs
    Smell alikestrong
    Cooked together1,832 recipes

    Shared aroma: coumarin (sweet, hay).

  2. Mustard + celerytop 2% of all pairs
    Smell alikemoderate
    Cooked together4,169 recipes

    Shared aroma: guaiacol (smoky, sweet).

  3. Pepper + lemontop 3% of all pairs
    Smell alikestrong
    Cooked together27,047 recipes

    Shared aroma: trans-2-nonenal (cardboard, fatty).

  4. Celery + lemontop 3% of all pairs
    Smell alikestrong
    Cooked together3,467 recipes

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

  5. Clove + peppertop 5% of all pairs
    Smell alikestrong
    Cooked together17,451 recipes

    Shared aroma: ethyl octanoate (fruity, wine).

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

What each ingredient does

Lemon rind
Adds aromatic oils and bright citrus flavour to the sauce.
Lemon juice
Adds acidity that sharpens the flavour and helps preserve the mixture.
Horseradish
Contributes a sharp, pungent heat that mellows during aging.
Mustard seed
Contributes pungency and a sharp, slightly bitter bite.

The step that matters

Boil the mixture for 30 minutes. Boiling extracts flavour from the spices and drives off excess moisture, while the long rest in a tightly corked bottle lets the flavours meld. Keep the bottle sealed during the month so the mixture stays stable.

Swap the mace

How well each one fits the dish's main ingredients (mustard, celery, clove, pepper, horseradish, lemon):

  1. Tarragonfits better
  2. Allspicefits better
  3. Dillfits better
  4. Macethe original

Fit is the average pairing score against mustard, celery, clove, pepper, horseradish, lemon. 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.

You might also like

Lemon SauceLemon Sauce236 recipesCream of Celery SoupCream of Celery Soup113 recipesCelery StewCelery Stew25 recipesHorseradish SauceHorseradish Sauce17 recipes