Why it works: Egg and lemon are a kitchen classic. They rank in the top 19% of all ingredient pairs, and cooks put them together in 44,316 recipes. Both carry (e,e)-2,4-decadienal, which smells fatty, deep fried. The science ↓
Plain Calf's Head Soup
Ingredients
Directions
Make the broth
Put a cleaned calf's head and a knuckle of veal into a large kettle.
Put one onion and a large tablespoon of sweet herbs into a cloth and add them to the kettle with the meat, then pour about four quarts of water.
If you wish to serve at one o'clock dinner, start boiling at eight o'clock in the morning; let it boil steadily and slowly, seasoning well with salt and pepper.
Finish and serve
About one hour before serving, remove the soup, pour it through a colander, pick out all the meat, chop it very finely, return it to the soup, and put it back over the fire.
Boil four eggs very hard, chop them finely, slice one lemon very thin, and add them at the very end.
Nutrition, whole recipe (rough)
Counts 3 of 4 ingredients. The other 1 aren't in our nutrition table and add nothing above, so the real totals are higher.
What these numbers assume: 3 portions
| Ingredient | Portion assumed | kcal |
|---|---|---|
| Egg | 1 large egg (50g) | 78 |
| Onion | 1 medium (110g) | 44 |
| 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.
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.
-
Egg + lemontop 19% of all pairsSmell alikelowCooked together44,316 recipes
Shared aroma: (e,e)-2,4-decadienal (fatty, deep fried).
-
Onion + lemontop 19% of all pairsSmell alikemoderateCooked together15,646 recipes
Shared aroma: decanal (soap, orange peel).
-
Onion + eggtop 34% of all pairsSmell alikelowCooked together23,333 recipes
Shared aroma: 2,4-decadienal (seaweed).
Egg and lemon barely smell alike, yet cooks put them together in 44,316 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
- Calf's head (in the method)
- Provides meat and gelatin that give the soup its body and rich flavor.
- Veal knuckle (in the method)
- Adds bone and connective tissue that enrich the broth with gelatin and savory depth.
- Eggs
- Hard-boiled and chopped, they add richness and a firm, soft texture to the soup.
- Lemon
- Thinly sliced, it adds acidity that brightens the rich broth.
The step that matters
Keep the boil steady and slow. A gentle, steady simmer draws flavor and gelatin from the bones and meat while keeping the broth clear. A hard rolling boil emulsifies fat into the liquid and makes it cloudy and greasy.
Swap the onion
How well each one fits the dish's main ingredients (egg, lemon):
- Asparagusfits better
- Spinachfits better
- Shallotfits better
- Onionthe original
Fit is the average pairing score against egg, lemon. 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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