extended agitation called conching, a process named after the shell-like shape of the first machines Conches rub and smear the mixture of cocoa liquor, sugar, and milk solids against a solid surface The combination of friction and supplemental heat raises the temperature of the mass to 115–175ºF/45–80ºC (milk chocolate is kept at 110–135ºF/43–57ºC) Depending on the machine and manufacturer, conching may last for 8 to 36 hours Refining Texture and Flavor The original conche was a mechanized version of the Mayan stone grinding slab: a heavy granite roller moved back and forth over a granite bed, both mixing the ingredients together and grinding the still somewhat coarse particles to a finer size Today the various solids are ground to the proper dimensions before conching, which now serves two main functions First, it breaks up small aggregates of the solid particles, separates them from each other, and coats all of them evenly with cocoa butter, so that when the finished chocolate melts, it flows smoothly Second, conching greatly improves the flavor of the chocolate, not by heightening it, but by mellowing it The aeration and moderate heat causes as much as 80% of the volatile aromatic compounds (and excess moisture) to evaporate out of the chocolate liquor Fortunately, many of these are undesirable volatiles, including various acids and aldehydes; acidity steadily declines during conching At the same time, a number of desirable volatiles are augmented by the heat and mixing, notably those with roasted, caramel, and malty aromas (pyrazines, furaneol, maltol) Both cocoa butter and a small amount of the emulsifier lecithin (p 802) are added to the chocolate mass toward the end of conching The additional cocoa butter is necessary to provide sufficient lubrication for ... mellowing it The aeration and moderate heat causes as much as 80% of the volatile aromatic compounds (and excess moisture) to evaporate out of the chocolate liquor Fortunately, many of these are... malty aromas (pyrazines, furaneol, maltol) Both cocoa butter and a small amount of the emulsifier lecithin (p 802) are added to the chocolate mass toward the end of conching The additional cocoa butter is...each other, and coats all of them evenly with cocoa butter, so that when the finished chocolate melts, it flows smoothly Second, conching greatly improves the flavor of the chocolate,