The jeweler cradles it in his hand, scrutinizing it through his eyepiece. "Flawless," he mutters, in a hushed, reverent voice. "A perfectly flawless crystalline structure." He brings it to his face. He opens his mouth. He eats it. "Delicious!"
Like a gem stone's luster, a chocolate bar's flavor depends largely on the crystalline structure of the chocolate's chemicals.
Research, sponsored by chocolate bar companies of course, has probed the secrets of chocolate at the molecular level. They have found that taste is dependent not only on what ingredients are used, but in how the molecules of those ingredients are arranged.
As it turns out, there are six distinct ways that cocoa butter, the main fat in chocolate, can crystallize. You can think of these different crystal forms as being like six different shapes of snowflake, only these shapes occur microscopically within the chocolate's fat.
A chocolate's crystal form determines not only how delicious it will be, but also how glossy it is, how sticky it is, how quickly it will melt in your mouth, and whether it will develop a grey coating called "fat bloom" that appears on some lower-quality chocolates.
This research has paid off for chocolate manufacturers. The type of crystal structure a chocolate bar has is a result of the chocolate's manufacturing process, how it is heated and cooled, and how the liquid chocolate is mixed. By pinpointing exactly the right temperatures and mixing strategies, such research can ensure a delicious crystal structure in every bite!