Why chocolate is tempered
The shine and the snap of a good bar come from tiny crystals of cocoa butter. Tempering is how chocolate makers choose the right ones.
Melt a bar of chocolate, let it set again on the counter, and you will notice it has changed. It is dull, maybe streaky, and it bends instead of snapping. Nothing was added or taken away. What changed was the way the cocoa butter set.
One fat, six shapes
Cocoa butter can harden into several different crystal structures — six are usually described. Only one of them, often called Form V, gives chocolate a glossy surface, a clean snap and a melt that starts right around the temperature of your mouth.
Heat, cool, warm again
Tempering steers the chocolate into that one crystal form. For dark chocolate the usual path is:
- Melt it completely, to around 45–50 °C, so no old crystals remain.
- Cool it, often to about 27–28 °C, while stirring, so new crystals start to form.
- Warm it gently to about 31–32 °C, which melts the unstable crystals and keeps the good ones.
Milk and white chocolate follow the same idea at slightly lower temperatures.
How to tell
Dip the tip of a knife and leave it at room temperature. Well-tempered chocolate sets within a few minutes, shiny and even. If it stays soft or turns grey and streaky, it needs another round.
