Why it works: Sugar and lemon are a kitchen classic. They rank in the top 18% of all ingredient pairs, and cooks put them together in 53,532 recipes. Both carry 2-nonenal, which smells fatty, green. The science ↓
Barley-Sugar
Ingredients
Directions
Make the syrup
Combine sugar and spring water in a large pot.
Add enough egg white to clarify the mixture.
Heat gently, stirring until it begins to whiten and thicken.
Finish and flavor
Once thick, add the lemon juice and boil quickly until it reaches the desired consistency.
Optionally, add a few drops of lemon essence for flavor.
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.
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Sugar + lemontop 18% of all pairsSmell alikelowCooked together53,532 recipes
Shared aroma: 2-nonenal (fatty, green).
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Egg + lemontop 19% of all pairsSmell alikelowCooked together44,316 recipes
Shared aroma: (e,e)-2,4-decadienal (fatty, deep fried).
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Sugar + eggtop 21% of all pairsSmell alikemoderateCooked together122,807 recipes
Shared aroma: 2-nonenal (fatty, green).
Sugar and lemon barely smell alike, yet cooks put them together in 53,532 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
- Highly-refined sugar
- Forms the bulk of the candy and sets into a hard, glassy mass as it cools.
- Egg white
- Clarifies the syrup, binding impurities so they can be skimmed away.
- Lemon juice
- Adds acidity that brightens the flavor and helps limit sugar crystallization.
The step that matters
Boiling quickly to the desired consistency. Sugar syrup hardens as its concentration rises, so overcooking makes the candy brittle or darkens it, while undercooking leaves it sticky and soft once cooled.
Swap the lemon
The recipe marks lemon as optional. How well each one fits the dish's main ingredients (sugar, egg):
- Vanillafits better
- Raisinfits about as well
- Lemonthe original
- Datesfits less well
Fit is the average pairing score against sugar, egg. 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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