CHANGES IN THE PHYSICOCHEMICAL PROPERTIES OF RICE EXTRUDATE DURING VACUUM EXTRUSION

Abstract

The article studies the influence of variables on the extrusion of rice flour using a vacuum extruder and compares it with conventional atmospheric extrusion. Variable analysis was carried out using the response surface methodology. The Statistica 10 program was used to design the experiment, perform the statistical analysis, and was used to design, evaluate effects, and obtain response surfaces. Extrusion mixtures were made from rice flour (50%) and brown rice flour (50%), and the moisture content varied from 25% to 35%. The independent variables of the extrusion process were: temperature, raw material moisture content, screw rotation speed and vacuum value. The dependent response variables were: bulk density, water absorption index and specific mechanical energy. All independent parameters had a significant effect on the bulk density. Increasing the vacuum level increases the water absorption index due to the formation of a porous structure. The moisture content of the mixture has a significant effect on the specific mechanical energy. it can be concluded that vacuum extrusion is an effective way to obtain expanded extrudates with modified physicochemical properties.