WASHINGTON — The secret of how the fruit got inside the liquid-filled, chocolate-covered cherries is almost as much of a mystery as how the ship got inside the bottle.
The process by which these unique candies are created relies on a chemical reaction that actually takes place after the candy is made, says Dr. David Chisdes, an American Chemical Society member affiliated with a major candy company.
Before being dipped in chocolate, the cherries are coated with a sugary paste containing an enzyme, called invertase, he explains. The paste hardens and the cherries are dipped in chocolate. Then they are stored for one to two weeks.
During this period the enzyme triggers a chemical reaction in the candy. One form of sugar, sucrose, is changed to two other more soluble forms: dextrose and fructose.
"In effect, the outer part of the cherry liquefies in its own syrup, leaving the cherry center swimming in liquid," Chisdes says. "This explains how these succulent candies can be made without there being a hole somewhere in the coating."
Commercial chocolate products are made by mixing together sugar, cocoa butter, milk powder and chocolate liquor made from ground cacao beans. The mixture is passed through a series of rollers until an optimum particle size is achieved.
"The size of the compressed particles is critical," Chisdes points out. "If they are too small, the chocolate will feel slimy in the mouth, and if they are too large, it will feel gritty."
Before chocolate is ready to be poured into a mold or used as a coating on a fruit or cream center, it must pass through heating, then cooling, cycles.
"This helps the cocoa butter to crystallize in a stable form," Chisdes says. "If it doesn't, as sometimes happens, a white or grayish tinge is visible on the chocolate surface.
"The general public usually considers this a sign of staleness," he adds, "but in fact it's only a crystal defect and has nothing to do with the age of the chocolate."
To keep chocolates from developing this condition--known as fat bloom--Chisdes advises storing them at room temperature.