Why it works: Onion and carrot are a kitchen classic. They rank in the top 6% of all ingredient pairs, and cooks put them together in 21,601 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
Ox-Tail Soup
Ingredients
Directions
Prepare the tails
Divide the ox tails at the joints.
Soak them in warm water.
Place the tails in a gallon pot and cover with cold water.
Skim off any froth that forms on the surface.
Simmer and finish
Boil the tails until the meat is tender and falls off the bones.
Remove the bones.
Add the chopped onion and carrot.
Season with spices and herbs as desired.
Thicken the soup with browned flour.
Boil for an additional 3 to 4 hours.
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.
-
Onion + carrottop 6% of all pairsSmell alikemoderateCooked together21,601 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Carrot + flourtop 13% of all pairsSmell alikemoderateCooked together8,029 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Onion + flourtop 17% of all pairsSmell alikemoderateCooked together32,460 recipes
Shared aroma: isobutyraldehyde (malty, green).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Ox tails
- Provide the meat, collagen and rich flavour that give the soup its body.
- Browned flour
- Thickens the soup as its starch swells in the hot liquid, and adds a toasted flavour.
- Onion
- Adds savoury depth and sweetness as it softens into the broth.
- Carrot
- Adds subtle sweetness and body to the broth as it cooks.
The step that matters
Skim off the froth. Foam rising at the start carries impurities and proteins that can make the broth cloudy and taste off. Removing it early keeps the soup clear and clean-flavoured.
Swap the onion
How well each one fits the dish's main ingredients (carrot, flour):
- Parsnipfits better
- Turnipfits better
- Arrowrootfits better
- Onionthe original
Fit is the average pairing score against carrot, 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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