Chocolate – What tempering process do you use when moulding chocolates

To answer your last question: yes.

Regarding the previous question, it's because the temperature at which the cocoa butter in the chocolate crystallizes affects the overall consistency of the chocolate. If you've ever eaten a chocolate bar that was left in a car on a hot day after it has cooled down again, and who hasn't, you'll know about this. Sometimes chocolate tastes fine but has a definite 'grittiness' to it: other things being equal, that's usually because the cocoa butter crystals are too large.

Cocoa butter has a number of different crystal forms, each of which will have a slightly different effect on texture and melting point. When melted chocolate sets, the cocoa butter crystallizes, and it will generally all crystallize with the structure that it starts to crystallize with. (This process where crystals start to grow is called nucleation.)

So you want to have control over the temperature at which crystallization starts. The optimum crystal form for nice chocolate will tend to predominate when crystallization starts somewhere between 18-25 degrees C (around 64-77F).

So if you think about it: when you add room temperature stuff (like a pretzel) to chocolate that is considerably hotter than room temperature, the resultant temperature on the surface of that pretzel will likely be way higher than 18-25 degrees. On the other hand, if you are dipping an item that is significantly below room temp, then your chances of hitting that window are much higher.

The surface structure of the thing being dipped can of course make a difference to crystallization as well, but for normal purposes that is marginal. To put it another way, it doesn't matter what ingredients you're dipping - temperature is key!

Chocolate will stay fresh for weeks or even months if stored correctly. And yes, the spheres will stay as shiny and beautiful as you made them if you store them correctly:

• in a cool, dark place away from sunlight
• but not necessarily in the fridge - taking them out will lead to condensation on the surface
• at rather constant temperature
• and dry.

So in short:
A large enough foodsafe plastic container in a cool cellar or cupboard, away from (sun-)light and, if applicable, curious kids, pets or others that might feast on your stash in advance. Unless you have a high humidity environment, it's not absolutely necessary that the box be airtight. But if you want to be really sure, include some silica gel packs against excess humidity.

Do not stack them like nested bowls, or you could scratch or otherwise damage the glossy surface. If you have to, place one layer in your box, cover with parchment, foil or similar, add a sheet of cardboard for stability and another layer of parchment or foil, then the next layer of spheres.

Good luck and have a good party!