| 摘要 |
Procedure for regulation of starch gelatinization and density of extruded foods and animal feed (fig. 1.0). The percentage (X) of the mixture desired to have extruder-cooked is continuously fed to the intake zone (A). If the mixture does not have sufficient moisture when fed to the intake zone (A), water and/or steam must be added and mixing must go on immediately after the intake. From the intake zone (A) the mixture is carried to the cooking zone (B), in which a high pressure is built up by forming a back-pressure from the extruder screw and from heating the extruder head to enhance the cooking process. From the cooking zone (B) the mixture is carried to the cooling zone (C), in which the pressure is reduced and the extruded mixture is cooled. From the cooling zone (C) the extruded mixture is led through the intake zone (D) where the other percentage (Y) of the mixture is continuously added u n heated. Upon addition of the unheated percentage (Y) the extruded part (X) and the unextruded part (Y) of the mixture is carried to a mixing zone (E), where the parts are mixed to a homogeneous mixture. From the mixing zone (E) the mixture (X+Y) is pressed towards a die (F), in which the form and size of the mixture are formed. |
