Rock Candy
Ingredients
Directions
Prepare the cans
Prepare three tin cans (14 x 12 x 18 inches) with holes 2 inches apart on the sides.
Run a string through the holes inside the cans, starting from the bottom.
Make flour paste and cover the outside of the cans with Manila paper to prevent syrup leakage.
Make the syrup
In a large pot, combine 10 lbs of cane sugar and 7 gallons of water. Cook while monitoring with a Saccharometer.
Start cooking at 30% on the Saccharometer and raise to 37%.
Grow the crystals
Pour the mixture into the prepared cans with strings inside and seal the outside.
Place the cans in a warm room (125°F to 130°F) for 48 hours.
Drain off the syrup and let the cans dry for 5-6 hours without syrup.
Remove the strings of Rock Candy from the cans.
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
What each ingredient does
- Cane sugar
- Forms the crystals that make up the candy and provides all of its sweetness.
- Water
- Dissolves the sugar so it can form a syrup that crystallizes as it cools and dries.
The step that matters
Raising the syrup concentration from 30% to 37% on the Saccharometer. The syrup must be concentrated enough to be supersaturated. As it cools in the warm room, excess sugar comes out of solution and clings to the strings, so the crystals grow. Too little sugar gives weak or no crystals.
“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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