Why it works: Tomato and pepper are a kitchen classic. They rank in the top 7% of all ingredient pairs, and cooks put them together in 17,923 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
Tomato Soup
Ingredients
Directions
Put the soup bone in a pot with 2 quarts of water and boil early.
Once done, remove the bone from the pot.
Pass the can of tomatoes through a sieve and add to the liquid.
Immediately add ½ teaspoon baking soda, a small lump of butter, 1 tablespoon of white sugar, and 1 heaping tablespoon of flour mixed with ½ cup of cream or milk.
Season with salt and pepper to taste.
After adding the flour mixture, let it boil three times and serve.
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.
Photo for illustrative purposes only · Contact us to use it
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.
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Tomato + peppertop 7% of all pairsSmell alikemoderateCooked together17,923 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Butter + creamtop 8% of all pairsSmell alikemoderateCooked together41,516 recipes
Shared aroma: delta-dodecalactone (sweet, creamy).
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Sugar + creamtop 9% of all pairsSmell alikemoderateCooked together43,450 recipes
Shared aroma: 2,3-butanedione (butter, sweet).
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Butter + flourtop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Sugar + flourtop 15% of all pairsSmell alikemoderateCooked together92,116 recipes
Shared aroma: phenylacetaldehyde (hawthorne, honey).
Butter and flour barely smell alike, yet cooks put them together in 124,287 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
- Tomatoes
- Provide the main flavor and body of the soup.
- Flour
- Thickens the soup as it heats, giving it a smoother body.
- Cream or milk
- Adds richness and softens the acidity of the tomatoes.
- Baking soda
- Neutralizes some of the tomato acidity and reduces sharpness.
The step that matters
Adding the baking soda to the tomatoes. Baking soda reacts with tomato acid and releases carbon dioxide, causing foaming and possibly overflow. Adding it immediately, while the mixture is hot, can cause it to bubble up quickly, so the pot should be large enough to hold the foam.
Swap the tomato
How well each one fits the dish's main ingredients (butter, sugar, flour, cream, pepper):
- Leekfits better
- Arrowrootfits better
- Capsicumfits better
- Tomatothe original
Fit is the average pairing score against butter, sugar, flour, cream, pepper. 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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