Why it works: Garlic and vinegar are a kitchen classic. They rank in the top 11% of all ingredient pairs, and cooks put them together in 9,115 recipes. Both carry acetic acid, which smells sour, vinegar. The science ↓
Tomato Catsup
Ingredients
Directions
Prepare the tomatoes
Gather the following ingredients: one bunch ripe tomatoes, ½ gallon vinegar, ½ pound sugar, ½ pint salt, 1½ ounces black pepper, 1½ allspice, 2 ounces mustard, 1 ounce ginger, ½ ounce cloves, ⅛ ounce cayenne, a little alcohol.
Boil tomatoes gently for half an hour, then press through a colander to remove skins and cores.
Return the liquid to a porcelain-lined kettle and boil down to half.
Season and reduce
Add vinegar, sugar, salt, and spices, then boil down to two thirds. The catsup is not so dark if boiled down to two thirds. After adding vinegar alone, then sugar, salt, and spices, let it come to a boil, then remove from the fire.
Optionally, add two small heads of garlic or a small onion chopped finely with the spices.
Bottle and seal
Bottle the catsup when perfectly cold, pouring a little alcohol into the top of each bottle.
Cork and seal the bottles.
Nutrition, whole recipe (rough)
What these numbers assume: 4 portions
| Ingredient | Portion assumed | kcal |
|---|---|---|
| Allspice | 1 tsp ground (1.9g) | 5 |
| Garlic | 1 clove (3g) | 4 |
| Vinegar | 1 tbsp (15ml) distilled | 3 |
| Salt | 1 tsp (6g) | 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.
-
Garlic + vinegartop 11% of all pairsSmell alikemoderateCooked together9,115 recipes
Shared aroma: acetic acid (sour, vinegar).
-
Allspice + garlictop 12% of all pairsSmell alikestrongCooked together1,379 recipes
Shared aroma: beta-phellandrene (minty, terpene).
-
Allspice + vinegartop 13% of all pairsSmell alikemoderateCooked together4,548 recipes
Shared aroma: 2-methylbutyl acetate (fruit).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Tomatoes (in the method)
- Form the bulk of the ketchup and supply its body, flavour and colour once reduced.
- Vinegar
- Adds acidity that sharpens the flavour and helps preserve the finished sauce.
- Sugar (in the method)
- Adds sweetness that balances the acidity and rounds out the spices.
- Black pepper (in the method)
- Provides a sharp, mildly hot spice note that adds depth to the sauce.
The step that matters
Boiling down to two thirds. Reducing too far or too little changes both thickness and colour. The record notes that boiling to two thirds keeps the catsup less dark, so stop at that volume rather than letting it darken and over-thicken.
Swap the allspice
How well each one fits the dish's main ingredients (garlic, vinegar):
- Tarragonfits better
- Cuminfits better
- Corianderfits better
- Allspicethe original
Fit is the average pairing score against garlic, 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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