Why it works: Butter and flour are a kitchen classic. They rank in the top 12% of all ingredient pairs, and cooks put them together in 124,287 recipes. Both carry isobutyraldehyde, which smells malty, green. The science ↓
Brown Roux
Ingredients
Directions
Make the roux
Dissolve the butter and skim off the impurities.
Pour the clear oily part into a saucepan over low heat.
Gradually add the flour to make a thick paste, stirring constantly.
Heat the mixture slowly until it becomes very thick and bright brown.
Store and use
Store in a jar and stir a spoonful into soup or gravy as needed.
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.
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Butter + flourtop 12% of all pairsSmell alikelowCooked together124,287 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
- Provides fat that coats the flour particles and carries flavour as the roux cooks.
- Fine flour
- Starch that thickens the fat into a paste and, as it browns, adds nutty flavour and colour.
The step that matters
Heating the roux slowly. Flour starch browns and thickens gradually over low heat. Rushing with high heat can scorch the starch before it develops colour and flavour, leaving a bitter taste, while constant stirring prevents lumps and burnt spots.
“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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