Why it works: Mustard and celery are a kitchen classic. They rank in the top 2% of all ingredient pairs, and cooks put them together in 4,169 recipes. Both carry guaiacol, which smells smoky, sweet. The science ↓
Mother's Tomato Catsup
Ingredients
Directions
Prepare the tomatoes
Cut a slit in the tomatoes. Place the tomatoes in a porcelain kettle.
Boil until all juice is extracted and pulp is dissolved.
Strain the tomatoes. Press through a colander. Press through a fine sieve.
Season and cook
Return to the fire. Add seasoning.
Boil for at least 5 hours, stirring constantly for the last half hour.
Rest and bottle
Let it stand for 12 hours in a stone jar in a cool place.
When cold, add 1 pint of strong vinegar. Remove the bag of celery seed.
Bottle the catsup. Seal the corks. Store in a dark, cool 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.
-
Mustard + celerytop 2% of all pairsSmell alikemoderateCooked together4,169 recipes
Shared aroma: guaiacol (smoky, sweet).
-
Tomato + celerytop 4% of all pairsSmell alikemoderateCooked together3,377 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
-
Pepper + clovetop 5% of all pairsSmell alikestrongCooked together17,451 recipes
Shared aroma: ethyl octanoate (fruity, wine).
-
Pepper + celerytop 5% of all pairsSmell alikestrongCooked together16,012 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
-
Clove + celerytop 6% of all pairsSmell alikestrongCooked together4,668 recipes
Shared aroma: gamma-decalactone (peach, creamy).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Ripe tomatoes
- Form the bulk of the sauce, providing body, moisture and most of the flavor.
- Salt
- Seasons the sauce and helps draw out moisture during the long simmer.
- Strong vinegar
- Adds acidity that sharpens flavor and helps preserve the finished ketchup.
- Ground mustard
- Adds a pungent, sharp note that balances the sweetness of the tomatoes.
The step that matters
Stirring during the final half hour of boiling. Thick tomato sauce scorches easily on the bottom of the pan as water evaporates and sugars concentrate. Constant stirring at the end prevents burning and gives an even, smooth texture.
Swap the mace
How well each one fits the dish's main ingredients (tomato, pepper, clove, mustard, celery, vinegar):
- Tarragonfits better
- Allspicefits better
- Thymefits better
- Macethe original
Fit is the average pairing score against tomato, pepper, clove, mustard, celery, 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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