Why it works: Flour and capers match in chemistry and in kitchens. They rank in the top 6% of all ingredient pairs, and cooks put them together in 1,024 recipes. Both carry isobutyraldehyde, which smells malty, green. The science ↓
Caper Sauce
Ingredients
Directions
In a saucepan, melt 1 ounce of butter over low heat.
Stir in 1 teaspoon of flour and add ½ cup of cold water.
Season with salt and pepper.
Place the saucepan on the back of the stove and stir occasionally until it boils.
Beat the mixture until smooth.
Add 2 ounces of butter and 1 tablespoon of capers.
Serve in a hot bowl.
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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Flour + caperstop 6% of all pairsSmell alikestrongCooked together1,024 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Butter + flourtop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Pepper + caperstop 12% of all pairsSmell alikemoderateCooked together2,088 recipes
Shared aroma: coumarin (sweet, hay).
-
Butter + caperstop 16% of all pairsSmell alikemoderateCooked together1,637 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Flour + peppertop 19% of all pairsSmell alikemoderateCooked together50,459 recipes
Shared aroma: isobutyraldehyde (malty, green).
Butter and flour barely smell alike, yet cooks put them together in 124,287 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
- Butter
- Enriches the sauce with fat for a smooth, rich texture and flavor.
- Flour
- Thickens the liquid into a smooth sauce as it heats.
- Capers
- Add a sharp, briny acidity that cuts through the butter.
The step that matters
Beat the mixture until smooth. Flour lumps form if it is not fully dispersed in the liquid. Beating while the sauce heats breaks up clumps so the starch thickens evenly into a smooth sauce.
Swap the capers
How well each one fits the dish's main ingredients (butter, flour, pepper):
- Parsleyfits better
- Turmericfits about as well
- Nutmegfits about as well
- Capersthe original
Fit is the average pairing score against butter, flour, 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.
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