Effects of twin-screw extrusion on soluble dietary fibre of jujube residue

Wei Zong, Jun Duan, Weiwei Zha

Abstract

Twin-screw extrusion technology was applied to increase the soluble dietary fibre (SDF) content in jujube residue. Response surface methodology was used to optimize the extrusion parameters. The effect of feed moisture, motor frequency and extrusion temperature on SDF content were evaluated. From the response surface contour plots and from the quadratic regression model equation，the optimal extrusion parameters were as follows: feed moisture 27.5%, motor frequency 34 Hz and extrusion temperature 164℃. Under these conditions, the SDF content of jujube residue could reach to 17.67%. Twin-screw extrusion can increase the SDF content of jujube residue.