Its all about Tempering

Tempering, in chocolate manufacturing, refers to the method of increasing the shine and durability of chocolate couverture. This is typically the final process while making the chocolate. This process results in the bright sheen and crisp bite of chocolate. It is important that cocoa butter is consistently crystallized  for smooth and small sized crystals which can not be seen with the naked eye. Else, our chocolate surface may appear mottled and matte, and this may cause the chocolate to crumble rather than snap when broken

The primary purpose of tempering is to assure that the fat in cocoa butter is glossy and firm and melts at body temperature. Anywhere between 28° C to about 36° C is the right temperature to melt the crystals.

Generally, the chocolate is first heated to 45 °C and then the chocolate is cooled to about 28 °C  which will allow crystals to form.  After this point, any excessive heating of the chocolate will destroy the temper and this process will have to be repeated. Manually, chocolate can be tempered by stirring solid chocolate into molten chocolate to “inoculate” the liquid chocolate with crystals.

Chocolate is very sensitive to temperature and humidity. Ideal temperatures to store it would be between 15 and 17 °C  and the  relative humidity of less than 50%. Chocolate is generally stored away from other foods to avoid mingling of different aromas. Additionally chocolate is frequently stored in a dark place or protected from light by wrapping paper. If chocolate is refrigerated or frozen without containment, chocolate can absorb enough moisture to cause a whitish discoloration. Alternately, moving  the chocolate from extreme cold to hot temperature can make the texture too oily.