It would be so handy if chocolate were like wax: You could melt it and cool it, and it would always have that same texture and appearance when it resolidified.
Sadly, it’s not that forgiving.
Good chocolate right out of the package has a nice snap and sheen. But when you melt it to use as a coating or for drizzling and leave it to resolidify, it can turn soft and take on a dull, dusty appearance.
This is because the crystal structure of the cocoa butter in the chocolate has changed. Cocoa butter can solidify into any of six different crystal formations, but only one—beta crystals—sets up firm and shiny.
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What Is Tempering Chocolate?
Chocolate with those qualities is known as tempered, and the traditional way to achieve it involves fussily heating, cooling, and reheating the chocolate to trigger beta crystal formation.
Melt a portion of the chocolate very gently in the microwave (faster, less fussy, and more efficient than a double-boiler setup), being careful not to let it get too warm. Then stir in the remaining chocolate, which has been finely grated with a box grater.
These small flakes disperse throughout the melted chocolate, and their temperature remains so low that most of their beta crystals remain intact. This triggers the formation of new crystals as the chocolate cools, so it becomes perfectly shiny and snappy.
How to Temper Chocolate in the Microwave
- Place three-quarters of chocolate, chopped fine, in bowl. Microwave at 50 percent power, stirring every 15 seconds, until melted but not much warmer than body temperature, about 93 degrees.
- Add remaining one-quarter of chocolate, grated on the small holes of a box grater (a microplane or a rotary grater works well, too), and stir until smooth, microwaving for no more than 5 seconds at a time, if necessary, to finish melting.
IT'S A SNAP:
Chocolate that’s been tempered is glossy and breaks cleanly if snapped.
LOST ITS TEMPER:
Chocolate that is melted and cooled without tempering will look dull and bend instead of breaking.