Tempering on a cool (marble) work surface
The purpose of tempering chocolate is to pre-crystallise the cocoa butter in the chocolate, which is related to the working temperature of the chocolate. During tempering, the cocoa butter in the chocolate changes into a stable crystalline form. It ensures the hardness, shrinking force and gloss of the finished product after it has cooled. If the chocolate is melted in the normal way (between 40 and 45 °C) then left to cool to working temperature, the finished product will not be glossy. If you make the effort of using a special way of bringing chocolate up to the right working temperature, you are guaranteed to get the desired end result. And that is what we mean by tempering: bringing chocolate up to the right working temperature so that there are sufficient stable crystals. The 3 factors which are important during tempering are time, temperature and movement.
Melt the chocolate at a temperature between 40 and 45 °C in a double boiler or melting pan.
Pour 2/3 of the melted chocolate onto the cool marble surface.
Keep the chocolate moving by stirring continually with a spatula and a scraper.
Continue to do so until the chocolate starts to thicken (when its temperature is 4 to 5 degrees lower than its working temperature): crystallisation takes place. You will see that 'peaks' are formed when the chocolate is allowed to fall from the spatula.
Pour the pre-crystallised chocolate into the rest of the melted chocolate and stir until it forms an even mixture.
The chocolate is now ready to work with. However, if the chocolate is too thick, reheat it until it becomes liquid again, but is still pre-crystallised. Take a sample: put the tip of a knife into the chocolate. If the chocolate is correctly tempered, it will harden evenly within 3 minutes at an ambient temperature of +/- 20 °C.
All chocolate should be tempered before you use it to
mould/pour, to use for creating blown figures, for coating cakes or
pralines. In short, whenever chocolate needs to have a perfect
sheen and be hard.
When you add chocolate to dishes to add flavour (when preparing mousses or Bavarian creams for instance), it usually suffices to melt the chocolate. Tempering is not required in these instances. All recipes will indicate clearly if the chocolate should be tempered or not.