Temperature

Form-V cocoa butter crystals melt if the chocolate is above 34°C/94°F, so chocolate must be below this threshold in order to contain Form-V seed crystals. If the chocolate is used at a temperature below 29°C/85°F, however, it is likely to contain not only Form-V crystals but also the unstable Form-IV crystals, which can result in reduced gloss and snap and a tendency to develop bloom during storage. While the optimum temperature at which dark chocolate should be used is approximately 32°C/90°F, the reality of tempering is such that, in order to form crystals relatively quickly, the chocolate is usually cooled to well below 32°C/90°F during seeding. (See Dark Chocolate Tempering Curve.) At this reduced temperature, both stable and unstable crystals are formed. After the chocolate is adequately seeded, the unstable crystals can be melted out by warming the chocolate for use, to approximately 32°C/90°F. Of the three factors required in chocolate tempering, temperature is the most easily measured.