In a nutshell, the process of tempering chocolate involves incorporating a small amount, typically 2-4%, of solid, stable cocoa butter crystals in melted chocolate. Cocoa butter is capable of solidifying into several different polymorphic forms, which, as they cool and set, affect the surface finish, setting time, snap and mouthfeel of the chocolate. It is important that the cocoa butter crystals in tempered chocolate are the correct polymorphic form; we call these stable cocoa butter crystals.
Three critical variables in chocolate tempering are: temperature, agitation, and time. Temperature is critical because cocoa butter crystals both form and melt at specific temperatures. Agitation is important because we want our cocoa butter crystals well distributed within the melted chocolate. Also the mixing keeps the cocoa butter crystals from growing too large before we want them to. Time is a significant factor, because it takes time for cocoa butter crystals to form and grow.
In the documents below, learn all about tempering chocolate, understanding bloom and working with compounds.