Why it works: Allspice and clove match in chemistry and in kitchens. They rank in the top 1% of all ingredient pairs, and cooks put them together in 7,874 recipes. Both carry estragole, which smells anise, licorice. The science ↓
Tomato Catsup
Ingredients
Directions
Prepare the tomatoes
Select firm, ripe tomatoes and wipe them with a damp cloth.
Slice the tomatoes into a porcelain-lined kettle.
Pour 3 pints of water over the tomatoes and add the sliced onions and peach leaves.
Boil until the tomatoes are soft, about 1 to 2 hours.
Strain the mixture through a coarse sieve and return the liquid to the kettle.
Cook the ketchup
Add the ground spices, salt, sugar, and vinegar to the liquid.
Mix well and set over the fire.
Boil slowly for 2 hours, stirring almost constantly to prevent burning.
Add cayenne pepper to taste.
Bottle and store
Fill bottles and seal.
Store in a cool, dry place.
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.
-
Allspice + clovetop 1% of all pairsSmell alikestrongCooked together7,874 recipes
Shared aroma: estragole (anise, licorice).
-
Allspice + nutmegtop 1% of all pairsSmell alikestrongCooked together3,331 recipes
Shared aroma: estragole (anise, licorice).
-
Clove + nutmegtop 1% of all pairsSmell alikestrongCooked together8,686 recipes
Shared aroma: estragole (anise, licorice).
-
Allspice + mustardtop 2% of all pairsSmell alikestrongCooked together1,928 recipes
Shared aroma: methyleugenol (clove, spice).
-
Onion + mustardtop 6% of all pairsSmell alikestrongCooked together9,259 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Tomatoes
- Provide the main body, pulp and flavour of the ketchup.
- Brown sugar
- Adds sweetness and balances the acidity of the vinegar.
- Vinegar
- Adds acidity that sharpens flavour and helps preserve the ketchup.
- White onions
- Add savoury depth and body as they soften during boiling.
- Mustard
- Adds sharp, pungent flavour that complements the tomatoes and spices.
The step that matters
Boil slowly while stirring almost constantly. The thick, sugary mixture scorches easily on the bottom of the kettle. Constant stirring and gentle heat prevent burning and keep the flavour clean during the long reduction.
Swap the tomato
How well each one fits the dish's main ingredients (allspice, onion, clove, sugar, mustard, vinegar, nutmeg):
- Horseradishfits better
- Shallotfits better
- Radishfits better
- Tomatothe original
Fit is the average pairing score against allspice, onion, clove, sugar, mustard, vinegar, nutmeg. 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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