Why it works: Pepper and onion are a kitchen classic. They rank in the top 11% of all ingredient pairs, and cooks put them together in 68,474 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
A Scotch Haggis
Ingredients
Directions
Prepare the stomach
Wash the sheep's stomach with cold water.
Turn the stomach inside out.
Scald the stomach quickly.
Scrape the stomach.
Soak the stomach in cold salt water until needed.
Prepare the filling
Parboil the liver, lungs, and heart.
Grate the liver.
Mince the lungs and heart finely.
Mince the suet.
Toast the oatmeal before the fire.
Mix all ingredients well.
Season with pepper and salt.
Add a little water used to boil the onions for flavor.
Fill and boil
Fill the stomach bag.
Sew the bag up.
Place the bag in a pan with boiling water to cover it.
Place a small plate underneath.
Prick the bag with a needle to prevent bursting.
Boil for 4-5 hours, keeping it covered with boiling water.
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.
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.
-
Pepper + oniontop 11% of all pairsSmell alikemoderateCooked together68,474 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Liver + oniontop 15% of all pairsSmell alikelowCooked together1,420 recipes
Shared aroma: furaneol (caramel, strawberry).
-
Liver + peppertop 21% of all pairsSmell alikemoderateCooked together2,375 recipes
Shared aroma: 2-nonenal (fatty, green).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Sheep's stomach
- Forms the bag that encloses the filling while it cooks.
- Sheep's liver
- Adds richness and a soft, moist texture to the filling.
- Sheep's lights
- Contributes bulk and a tender, moist texture to the filling.
- Sheep's heart
- Adds savoury depth and a firm, meaty texture to the filling.
- Suet
- Adds fat that keeps the filling moist and rich as it cooks.
- Round oatmeal
- Absorbs juices and fat, giving the filling its crumbly body.
The step that matters
Prick the bag with a needle. Steam builds up inside the sealed stomach as it cooks, and without pricking the bag can burst. Keeping it fully covered with boiling water maintains steady heat.
Swap the onion
How well each one fits the dish's main ingredients (liver, pepper):
- Capsicumfits better
- Carrotfits better
- Mustardfits about as well
- Onionthe original
Fit is the average pairing score against liver, 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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