Why it works: Butter and milk are a kitchen classic. They rank in the top 7% of all ingredient pairs, and cooks put them together in 81,283 recipes. Both carry (z)-4-heptenal, which smells biscuit, cream. The science ↓
Tomato Soup
Ingredients
Directions
Make the tomato base
Take two and one half quarts of soup stock well seasoned with salt and pepper.
Thicken with three tablespoons of flour well mixed with a half cup of butter.
Then add two quarts of tomatoes which have been boiled and strained through a sieve.
Boil five minutes, then serve immediately.
Prepare the milk and tomatoes
Stew one quart can of tomatoes.
While the tomatoes are stewing, put three pints of milk on to boil, setting the dish into another of hot water.
When the milk comes to a boil, stir in a tablespoon full of flour which has been mixed with little cold milk.
Boil ten minutes, then add butter the size of an egg, salt and pepper to taste.
Add a pinch of saleratus to the tomatoes and strain into the mixture.
Nutrition, whole recipe (rough)
Counts 6 of 7 ingredients. The other 1 aren't in our nutrition table and add nothing above, so the real totals are higher.
What these numbers assume: 6 portions
| Ingredient | Portion assumed | kcal |
|---|---|---|
| Flour | 1 cup (125g) all-purpose | 455 |
| Milk | 1 cup (244ml) whole | 149 |
| Butter | 1 tbsp (14g) | 102 |
| Tomato | 1 medium (123g) | 22 |
| Black Pepper | 1 tsp ground (2.3g) | 6 |
| Salt | 1 tsp (6g) | 0 |
| Soup | not in our table | 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.
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.
-
Butter + milktop 7% of all pairsSmell alikemoderateCooked together81,283 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
-
Tomato + peppertop 7% of all pairsSmell alikemoderateCooked together17,923 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Flour + buttertop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Flour + milktop 14% of all pairsSmell alikelowCooked together78,219 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Tomato + milktop 15% of all pairsSmell alikemoderateCooked together2,226 recipes
Shared aroma: 1-octen-3-one (mushroom, metallic).
Flour and butter 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
- Flour
- Thickens the soup stock and milk into a smoother, heavier body.
- Butter
- Adds richness and a silky mouthfeel to the soup.
- Tomatoes
- Provide the main body, acidity and flavor of the soup.
- Milk
- Adds creaminess and softens the acidity of the tomatoes.
- Soup stock
- Provides the savory liquid base that carries the other ingredients.
The step that matters
Adding the milk. Acidic tomatoes can curdle hot milk. Heating the milk gently in a water bath and adding the tomatoes carefully helps keep the soup smooth.
Swap the tomato
How well each one fits the dish's main ingredients (flour, butter, milk, pepper):
- Potatofits better
- Capsicumfits better
- Chivefits better
- Tomatothe original
Fit is the average pairing score against flour, butter, milk, 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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