Why it works: Ketchup and flour are a kitchen classic. They rank in the top 13% of all ingredient pairs, and cooks put them together in 2,435 recipes. Both carry ethanol, which smells alcoholic, ethereal. The science ↓
Beef Kidney
Ingredients
Directions
Prepare
Cut the kidney into slices.
Season with coarse sea salt and ketchup.
Cook
Brown in a frying pan.
Add a little flour and water.
Let it stew gently for some time.
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.
Photo for illustrative purposes only · Contact us to use it
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.
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Ketchup + flourtop 13% of all pairsSmell alikemoderateCooked together2,435 recipes
Shared aroma: ethanol (alcoholic, ethereal).
-
Beef + ketchuptop 22% of all pairsSmell alikelowCooked together1,067 recipes
Shared aroma: ethanol (alcoholic, ethereal).
-
Beef + flourtop 25% of all pairsSmell alikelowCooked together10,677 recipes
Shared aroma: isobutyraldehyde (malty, green).
Beef and flour barely smell alike, yet cooks put them together in 10,677 recipes: they 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
- Beef kidney
- Forms the main body of the dish and is cooked until tender in the sauce.
- Ketchup
- Adds sweetness and acidity, and helps colour and flavour the sauce.
- Flour
- Thickens the cooking liquid into a light sauce that clings to the kidney.
The step that matters
Browning the kidney. Searing the slices in a hot pan builds browned, savoury flavour through the Maillard reaction. Crowding the pan or leaving the meat wet causes steaming instead, which gives a grey, bland surface.
“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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