Rheological properties of extruded dispersions of flaxseed-maize blend


WU M., Lİ D., WANG L., ÖZKAN N. , Mao Z.

JOURNAL OF FOOD ENGINEERING, vol.98, no.4, pp.480-491, 2010 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 98 Issue: 4
  • Publication Date: 2010
  • Doi Number: 10.1016/j.jfoodeng.2010.01.031
  • Title of Journal : JOURNAL OF FOOD ENGINEERING
  • Page Numbers: pp.480-491
  • Keywords: Rheological properties, Extrusion, Flaxseed-maize paste, EXTRUSION-COOKING, STRUCTURAL CHARACTERISTICS, CREEP-RECOVERY, WHEAT DOUGH, RICE FLOUR, STARCH, PROTEIN, FOOD, COMPONENTS, VISCOSITY

Abstract

Rheological properties of the extruded pastes of various extrusion conditions were investigated by dynamic oscillation and creep-recovery tests. Temperature sweep test showed that the starch gelatinization of non-extruded pastes took place at about 67 degrees C and no gelatinization was observed for the extruded sample. Frequency sweep tests could be represented by a Power law model and the samples showed gel-like behavior since storage modulus was much larger than loss modulus. The creep-recovery data were modeled by the Burger's model. With the addition of flaxseed, the viscoelastic modulii of pastes were increased due to the formation of starch-protein-fat network, however, with further increasing the flaxseed content the viscoelastic modulii of pastes were decreased due to excessive fat which lead to network weakening. The water holding capacity results indicated that the viscoelastic properties of pastes were depended on the swelled starch-protein complex granules and the formation of new cross-links in the network. (C) 2010 Elsevier Ltd. All rights reserved.