Emulsions and Crystals: Tempered Chocolate

Today, we experimented further with the concepts of emulsions and crystallization.  Chocolate served as the perfect vehicle; it is an emulsion because it consists of polar and nonpolar components that ordinarily would not mix, and the sugar particles in it are subject to crystallization.  To both maintain the emulsion and prevent crystals, chocolate must be tempered as it is melted and reformed.  Tempering provides the finished product with a uniform consistency and a satisfying, smooth crack when broken.

Tempering chocolate means raising the temperature slowly to a certain point, then cooling it back down into a form.  The point of this is to make sure all of the particles are the same size and shape.  I read one analogy for the process that I think sums it up nicely: if the particles are like bricks, you want all the bricks to be the same size and shape before building a house.  This is what the tempering process achieves.

The easiest way to temper is to seed.  This process is basically adding tempered chocolate to melted chocolate and proceeding to stir till your arm falls off.  Not really, but you stir a lot.  Melt the untempered chocolate to 115 degrees F, then add in the tempered chocolate.  I used a baking chocolate and a high quality tempered German chocolate.  After adding the chocolate, stir with a spoon or spatula (VIGOROUSLY) until the mixture cools to about 90 degrees F.  Then you are ready to pour the chocolate into its desired shape.  We used ours as the outer coating for cake balls!

The typical cake ball recipe calls for 2/3 of a cup of frosting for a 9x13 inch cake.  Crumble the cake, combine the two, and form into balls.  Freeze the balls, then dip into a coating (chocolate...mmm).  We used the scraps from the six egg cake and some of the extra chocolate frosting, so our ratio wasn't exact.  They worked fine either way.  Incidentally, beating the mixture with an electric mixer yielded a very fine cake ball dough.

After dipping, we topped the balls with sprinkles and cooled them in the fridge.  We had a large quantity of crisply coated cake balls, which the track girls thoroughly enjoyed.