Why it works: Butter and onion are a kitchen classic. They rank in the top 15% of all ingredient pairs, and cooks put them together in 42,912 recipes. Both carry decanal, which smells soap, orange peel. The science ↓
German Method of Clarifying and Preserving Fresh Butter
Ingredients
Directions
Set a large clean tinned copper vessel on a trivet over a charcoal fire.
Add the fresh butter before it has taken any ill taste, in small portions.
Add the onion to the butter.
Watch closely and skim the butter as soon as it begins to boil.
Slacken the fire to let it simmer for 5 minutes.
If not removed suddenly, extinguish the fire.
Remove the onion and let the butter stand until impurities sink to the bottom.
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 + oniontop 15% of all pairsSmell alikemoderateCooked together42,912 recipes
Shared aroma: decanal (soap, orange peel).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Butter
- Melting separates the milk solids and water from the butterfat, leaving a clear, pure fat.
- Onion
- Adds a light aroma to the butter while it heats and is removed before the fat is used.
The step that matters
Skimming as the butter begins to boil. Butter contains water and milk solids that foam and can scorch when it boils. Skimming promptly removes this foam, and holding the fire low keeps the solids from browning or burning on the bottom of the vessel.
“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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