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 ↓
Mom's Greaseless Meatloaf
Ingredients
Directions
Prepare the mixture
Place ground beef in a large mixing bowl.
In a separate bowl, mix ketchup, egg, salt, pepper, and dried mustard.
Combine ground beef with the mixture.
Knead by hand until well mixed.
Add finely chopped onion and bell pepper; knead by hand again.
Add oats a little at a time, kneading until the mixture is firm enough to form 1 or 2 small football shapes (about 6–8 inches long and 3–4 inches round).
Brown and pressure cook
Place the football-shaped loaf(s) in a skillet over medium heat and brown lightly on top and bottom, turning carefully to avoid burning.
Once browned, remove from skillet and transfer to a pressure cooker with a cooking grate at the bottom.
Add enough water to cover the grate by about ½ inch.
Optionally place a little ketchup along the top of the meat.
Cook in the pressure cooker according to the manufacturer's instructions.
When the pressure cap begins to rock, lower the heat to just enough for the rocker to move slowly.
Allow the rocker to go for 25–30 minutes.
Remove from heat and let cool until it is safe to remove the lid.
Nutrition, whole recipe (rough)
What these numbers assume: 9 portions
| Ingredient | Portion assumed | kcal |
|---|---|---|
| Beef | 100g cooked | 250 |
| Oat | 1/2 cup dry (40g) | 154 |
| Egg | 1 large egg (50g) | 78 |
| Onion | 1 medium (110g) | 44 |
| Bell Pepper | 1 medium (119g) | 31 |
| Tomato | 1 medium (123g) | 22 |
| Black Pepper | 1 tsp ground (2.3g) | 6 |
| Mustard | 1 tsp (5g) yellow | 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.
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.
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Onion + mustardtop 6% of all pairsSmell alikestrongCooked together9,259 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Beef + oniontop 7% of all pairsSmell alikemoderateCooked together17,092 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Pepper + mustardtop 9% of all pairsSmell alikemoderateCooked together15,430 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Beef + peppertop 10% of all pairsSmell alikemoderateCooked together18,971 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Onion + peppertop 11% of all pairsSmell alikemoderateCooked together68,474 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Ground beef
- Provides the main meaty body and fat that keeps the loaf moist while cooking.
- Egg
- Binds the meat and sets during cooking to hold the loaf together.
- Quick oats
- Absorb juices and fat, helping the loaf stay moist and firm.
- Ketchup
- Adds moisture and sweetness, and browns on the surface of the loaf.
- Onion
- Adds aroma and moisture as it softens during cooking.
The step that matters
Adding the oats. Adding oats a little at a time lets you judge when the mixture is firm enough to shape. Too much makes the loaf dense and dry, while too little leaves it too soft to hold its shape.
Swap the mustard
How well each one fits the dish's main ingredients (beef, egg, onion, pepper, ketchup, oats):
- Capsicumfits better
- Leekfits better
- Chivefits better
- Mustardthe original
Fit is the average pairing score against beef, egg, onion, pepper, ketchup, oats. 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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