Why it works: Onion and mustard match in chemistry and in kitchens. They rank in the top 6% of all ingredient pairs, and cooks put them together in 9,259 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
Meatloaf IV
Serves 8Ingredients
Directions
Prepare the mixture
Preheat oven to 325°F.
Combine beaten eggs, milk, mustard, onion, Parmesan cheese, parsley, pepper, and salt, then add bread cubes.
Crumble beef into mixture. Fold meat and sauce mixture together.
Shape and bake
Heavily spray a 9 x 13-inch glass baking dish or Dutch oven with cooking spray.
Form meat into a loaf shape in pan no more than 3 inches high.
Cover with ketchup, even if it takes more than ½ cup.
Bake 75 minutes or more, if desired.
Nutrition, whole recipe (rough)
What these numbers assume: 12 portions
| Ingredient | Portion assumed | kcal |
|---|---|---|
| Flour | 1 cup (125g) all-purpose | 455 |
| Beef | 100g cooked | 250 |
| Milk | 1 cup (244ml) whole | 149 |
| Parmesan Cheese | 1 oz (28g) | 110 |
| Egg | 1 large egg (50g) | 78 |
| Onion | 1 medium (110g) | 44 |
| Tomato | 1 medium (123g) | 22 |
| Soy Sauce | 1 tbsp (15ml) | 9 |
| Black Pepper | 1 tsp ground (2.3g) | 6 |
| Mustard | 1 tsp (5g) yellow | 3 |
| Parsley | 1 tbsp chopped fresh (3.8g) | 1 |
| 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.
Steps grouped into stages for easier reading; the method is the source's own.
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.
-
Onion + mustardtop 6% of all pairsSmell alikestrongCooked together9,259 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Wheat + milktop 6% of all pairsSmell alikemoderateCooked together2,418 recipes
Shared aroma: (e,z)-2,6-nonadienal (cucumber, melon).
-
Parsley + mustardtop 8% of all pairsSmell alikestrongCooked together2,588 recipes
Shared aroma: trans-2-hexenal (green, leafy).
-
Onion + parsleytop 9% of all pairsSmell alikemoderateCooked together25,843 recipes
Shared aroma: 2,4-decadienal (seaweed).
-
Wheat + breadtop 10% of all pairsSmell alikestrongCooked together209 recipes
Shared aroma: 2-acetyl-1-pyrroline (popcorn, roasted).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Eggs
- Bind the mixture and help the loaf hold its shape as it sets.
- Bread
- Soaks up milk and juices, keeping the meatloaf moist and tender.
- Ground beef
- Forms the main body of the loaf and provides its savory, meaty flavor.
- Milk
- Adds moisture to the bread and meat mixture for a softer texture.
- Parmesan cheese
- Adds savory, salty flavor and helps bind the mixture.
- Onion
- Adds moisture and sweetness that deepens as it cooks.
The step that matters
Form the loaf no more than 3 inches high. A loaf that is too tall cooks unevenly, leaving the center underdone while the outside dries out. Keeping it low lets heat reach the middle more evenly.
Swap the parsley
How well each one fits the dish's main ingredients (wheat, bread, egg, onion, milk, parmesan cheese, mustard):
- Capersfits better
- Garlicfits better
- Celeryfits better
- Parsleythe original
Fit is the average pairing score against wheat, bread, egg, onion, milk, parmesan cheese, mustard. 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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