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 ↓
Lemon Sauce
Ingredients
Directions
Prepare
Grate the rind of 1 lemon.
Add the juice of 1 lemon and 1 tablespoon of butter.
Make the sauce
Boil two cups of hot water and one cup of sugar for 5 minutes.
Add the flour wet with a little cold water.
Cook for 8 or 10 minutes.
Add the lemon rind, juice and butter, stir until butter is melted.
Serve
Serve at once.
Nutrition, whole recipe (rough)
Counts 4 of 5 ingredients. The other 1 aren't in our nutrition table and add nothing above, so the real totals are higher.
What these numbers assume: 4 portions
| Ingredient | Portion assumed | kcal |
|---|---|---|
| Flour | 1 cup (125g) all-purpose | 455 |
| Butter | 1 tbsp (14g) | 102 |
| Sugar | 1 tbsp (12.5g) granulated | 49 |
| Lemon | juice of 1 lemon (48ml) | 12 |
| Water | not in our table | 0 |
One typical portion per ingredient; the recipe's quantities are not counted. A rough guide only, not for medical or dietary planning.
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. See the original page.
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.
-
Butter + flourtop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Sugar + flourtop 15% of all pairsSmell alikemoderateCooked together92,116 recipes
Shared aroma: phenylacetaldehyde (hawthorne, honey).
-
Butter + lemontop 16% of all pairsSmell alikemoderateCooked together41,227 recipes
Shared aroma: 3-hexenal (apple, fruity).
-
Flour + lemontop 17% of all pairsSmell alikemoderateCooked together30,404 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Sugar + buttertop 17% of all pairsSmell alikemoderateCooked together98,233 recipes
Shared aroma: guaiacol (smoky, sweet).
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
- Sugar
- Sweetens the sauce and thickens it as it dissolves into the hot water.
- Flour
- Thickens the sauce as its starch swells in the hot liquid.
- Butter
- Adds richness and a smooth, glossy finish to the sauce.
- Lemon
- Supplies juice for sharp acidity and rind for aromatic lemon flavour.
The step that matters
Add the flour wet with a little cold water. Flour dropped into hot liquid dry clumps instead of dispersing. Mixing it smooth with cold water first lets the starch spread evenly, so the sauce thickens without lumps.
Swap the lemon
How well each one fits the dish's main ingredients (sugar, butter, flour):
- Raisinfits better
- Vanillafits better
- Figfits better
- Lemonthe original
Fit is the average pairing score against sugar, butter, flour. 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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