A chocolate tempering machine is a countertop electronic mixing and heating pan or appliance that is designed to take all the guesswork and manual labor out of tempering chocolate. It heats the chocolate to the correct temperature while constantly mixing it, allowing special crystalline shapes to form within the molecular structure. This gives the final product an attractive look and smooth taste.
Raw chocolate that is melted to make candy must be tempered to be crisp and smooth. If not tempered, chocolate dries to a very dull, unattractive and uneven color, streaked with gray. Moreover, it will be chalky and feel grainy on the tongue.
A chocolate tempering machine solves this problem by automating a process that causes the molecular crystals of the chocolate to take on a specific uniform structure, called a Beta V form. It heats the chocolate to a very precise temperature, then cools it slightly before reheating it, all while mixing the chocolate in a regulated manner. The combination of heating to the exact temperature — which is different for semi-sweet chocolate, milk, and white chocolate — and mixing just the right amount, causes the proper crystals to form.
A computer-controlled appliance can keep chocolate in the tempered, melted stage for hours at a time, allowing a chocolatier to make candies without tending to the tempering process itself. When the chocolate cools, it will be even colored, shiny, and crisp, yet will melt to a smooth, creamy consistency on the tongue.
To temper chocolate without a machine, a cook must use a double boiler, a candy thermometer that can register temperatures as low as 82.4°F (28°C), and a rubber spatula. Even tiny variations in the temperature of the chocolate will spoil the outcome, however, and over-mixing will cause the fats to separate, while under-mixing will prevent the Beta V crystals from forming. Even if the chocolate is tempered successfully, the chocolatier must keep moving it on and off the heat to keep it tempered, all while making the candy at the same time.
People who have made homemade chocolates without a chocolate tempering machine will likely appreciate the work this appliance does and how they are left free to enjoy the candy-making process.