Why it works: Parsley and onion are a kitchen classic. They rank in the top 9% of all ingredient pairs, and cooks put them together in 25,843 recipes. Both carry 2,4-decadienal, which smells seaweed. The science ↓
Boiled Fish
Ingredients
Directions
Prepare
Remove the head, fins, tail, and skin from the fish if dark and unsightly.
Wrap the fish in cheesecloth and baste the edges together.
Poach
In a fish kettle or large kettle, pour enough boiling water to cover the fish.
Add ¼ teaspoon coarse sea salt, 1 bay leaf, 1 sprig parsley, 1 slice of onion, and 1 tablespoon vinegar for each cup of water.
Simmer gently for 6 to 10 minutes per pound, depending on thickness.
When done, drain, remove from cheesecloth, and serve hot.
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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Parsley + oniontop 9% of all pairsSmell alikemoderateCooked together25,843 recipes
Shared aroma: 2,4-decadienal (seaweed).
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Onion + vinegartop 14% of all pairsSmell alikemoderateCooked together18,226 recipes
Shared aroma: acetic acid (sour, vinegar).
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Parsley + vinegartop 16% of all pairsSmell alikemoderateCooked together6,477 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
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Fish + parsleytop 18% of all pairsSmell alikelowCooked together2,341 recipes
Shared aroma: 2,4-decadienal (seaweed).
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Fish + oniontop 19% of all pairsSmell alikelowCooked together1,924 recipes
Shared aroma: 2,4-decadienal (seaweed).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Fish
- Forms the main body of the dish, cooked gently in simmering liquid until it turns opaque and flakes.
- Vinegar
- Adds a light acidity that brightens the flavor of the poaching liquid.
The step that matters
Simmer gently. Keeping the liquid at a gentle simmer rather than a hard boil cooks the fish evenly and keeps its flesh tender and intact. Vigorous boiling can break the fish apart and toughen the protein.
Swap the parsley
How well each one fits the dish's main ingredients (fish, onion, vinegar):
- Garlicfits better
- Tarragonfits better
- Capersfits better
- Parsleythe original
Fit is the average pairing score against fish, onion, vinegar. 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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