Why it works: Grape and lemon are a kitchen classic. They rank in the top 14% of all ingredient pairs, and cooks put them together in 2,412 recipes. Both carry 3-hexenal, which smells apple, fruity. The science ↓
Water-melon Rind
Ingredients
Directions
Prepare the rind
Cut the watermelon rind into fanciful shapes with a sharp knife.
Weigh the rind and use 1.5 pounds of sugar for every pound of rind.
Soak the rind in weak alum water for 3 days.
Soak the rind in clear water for 24 hours.
In a kettle lined with grape leaves, layer the rind and cover with water.
Simmer the rind for 2 hours.
Spread the rind on dishes to cool.
Make the syrup
In the kettle, combine sugar with 1 pint of water for every 1.5 pounds of sugar and the beaten egg whites.
Boil the mixture.
Skim off the egg and strain the syrup.
Wipe out the kettle.
Return the syrup to the kettle and bring it to a boil.
Add the rind and cook for 2 hours.
Remove the rind.
Boil the syrup again.
Pour the syrup over the rind.
Finish and serve
The next day, pour off the syrup.
Boil the juice of 1 lemon for every quart of syrup.
When thick, pour the lemon juice over the rind and tie it up.
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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Grape + lemontop 14% of all pairsSmell alikemoderateCooked together2,412 recipes
Shared aroma: 3-hexenal (apple, fruity).
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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).
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Sugar + grapetop 23% of all pairsSmell alikelowCooked together7,490 recipes
Shared aroma: beta-damascenone (apple, rose).
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
- Watermelon rind
- Forms the candied piece itself, absorbing syrup to become translucent and sweet.
- Loaf sugar
- Sweetens the rind and, at high concentration, preserves it by drawing out water.
- Alum water
- Firms the rind's texture so it holds its shape during long simmering.
- Egg whites
- Bind impurities into a foam that can be skimmed off, clarifying the syrup.
- Lemon juice
- Adds acidity that brightens the sweetness and helps balance the syrup.
The step that matters
Soaking and simmering the rind before syrup. The rind must be fully softened and cooked through before it takes up sugar. Skipping or shortening the soaks and simmer leaves it tough, and the syrup cannot penetrate evenly.
Swap the grape
How well each one fits the dish's main ingredients (sugar, egg, lemon):
- Orangefits better
- Vanillafits better
- Limefits better
- Grapethe original
Fit is the average pairing score against sugar, egg, lemon. 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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