A special heating-mixing unit is used to heat the chocolate for a period of 12 - 24 hours at around 90º C and chocolates of high quality are conched up to 72 hours. The cocoa butter continuously flows from the openings settling evenly on the chocolate, during the process, thereby ensuring a sifter, liquid coating. Heat and infusion of oxygen results in desiccation of chocolate and only one percent moisture remains in the final setting of the chocolate. Undesirable entities and residues and bitter substances - organic compounds like acetaldehyde, acetone, ethanol, i-propyl alcohol, i-butyl alcohol, i-pentanal, diacetyl, ethyl acetate acetic acid, methanol, etc - are then removed. More cocoa is added to the chocolate after the conching process, if the need arises.