Why it works: Flour and butter 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 and White Thickening, or Roux
Ingredients
Directions
Prepare
Ensure the flour is thoroughly dry and sift it.
Squeeze the butter in a cloth to remove as much moisture as possible.
Melt the butter
Melt the butter in a stew-pan until it runs to oil.
Allow the froth to rise to the top.
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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Flour + buttertop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
Flour and butter 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
- All-purpose flour
- Provides starch that thickens the roux and gives it structure as it cooks.
- Butter
- Supplies fat that coats the flour and carries richness and flavor through the roux.
The step that matters
Remove as much moisture from the butter as possible. Water in butter causes spattering and can make the roux clump or steam instead of cooking in fat. Squeezing it out in a cloth lets the flour cook evenly in the fat.
“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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