Name: Brown Sauce for Fish
Ingredients: butter; liver (boiled and pounded); 1 egg yolk; flour; 1 teaspoon ketchup; 1 teaspoon soy sauce

Why it works: Ketchup and sauce match in chemistry and in kitchens. They rank in the top 1% of all ingredient pairs, and 1,099 recipes mention both. Both carry ethanol, which smells alcoholic, ethereal. The science ↓

Brown Sauce for Fish

Ingredients

Directions

Melt some butter in a saucepan.
Add the boiled and pounded liver.
Thicken the mixture with the egg yolk and flour.
Season with ketchup and soy sauce.

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 aroma chemistry they share, and how many recipes mention both.

Ketchup + saucetop 1% of all pairs

Aroma overlapstrong

Mentioned together1,099 recipes

Shared aroma: ethanol (alcoholic, ethereal).
Butter + flourtop 12% of all pairs

Aroma overlaplow

Mentioned together124,287 recipes

Shared aroma: isobutyraldehyde (malty, green).
Flour + ketchuptop 13% of all pairs

Aroma overlapmoderate

Mentioned together2,435 recipes

Shared aroma: ethanol (alcoholic, ethereal).
Butter + saucetop 15% of all pairs

Aroma overlaplow

Mentioned together15,338 recipes

Shared aroma: ethanol (alcoholic, ethereal).
Egg + flourtop 15% of all pairs

Aroma overlaplow

Mentioned together106,462 recipes

Shared aroma: isobutyraldehyde (malty, green).

Butter and flour share little aroma chemistry, yet 124,287 recipes mention both: they likely work on texture and structure more than aroma.

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

What each ingredient does

Butter: Melts to form the fat base that carries the sauce's flavour and gives it richness.
Liver: Provides the main body and savoury, meaty flavour of the sauce.
Egg yolk: Thickens the mixture and helps it turn smooth and creamy as it sets.
Flour: Helps thicken the sauce by absorbing liquid and giving it body.

“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.