Dutching cocoa to obtain rich colour product - by forming cocoa powder, mixing with alkali feeding mixture to combined cooker and pressurised extruder and pelletising the compsn

摘要

A process for the continuous dutching and drying of cocoa comprises (a) pulverising a press cake or nibs of cocoa material into a free-flowing powder state; (b) forming an aq. alkaline soln. contng. 3-12 wt.% NH3 or alkali(ne earth) metal salt; (c) combining the soln, with the pulverised material and diluting with water, to form a damp mass having an initial moisture content of 20-35% and =6 wt.% alkaline equivalent to K2CO3 and forming a homogeneous product mixture, (d) cooling the mixture at 150-230 degrees F. for 2 1/2 to 5 min. and while still mixing, progressively increasing the pressure to a final 500-1300 psi. to form a heated and pressurised mass; (e) extruding the resultant mass through a die means to form a product rod; (f) dividing the product into lengths to form pellets, having an 85-97% initial moisture content; and (g) drying the product pellets on a fluidised bed, by contacting with a heated inert gas at 350-450 degrees F. for 2.5 to 3 min., and then rapidly cooling the pellets with filtered air to ambient temp., the pellets having a moisture content of 4%, whereby dutching is crried out in a controlled fashion without interruption. The cocoa obtd. has a rich colour, and favourable taste, pH factor, water absorption and viscosity, low, microbial flora, etc.