Rheological properties of dilute aqueous solutions of cassava starch


Che L., Li D., Wang L., ÖZKAN N. , Chen X. D. , Mao Z.

CARBOHYDRATE POLYMERS, vol.74, no.3, pp.385-389, 2008 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 74 Issue: 3
  • Publication Date: 2008
  • Doi Number: 10.1016/j.carbpol.2008.03.007
  • Title of Journal : CARBOHYDRATE POLYMERS
  • Page Numbers: pp.385-389
  • Keywords: rheological properties, cassava starch, solution, TAPIOCA STARCH, DISPERSIONS, BEHAVIOR, GRANULE, GELATINIZATION, TEMPERATURES, GELATION, GLUCOSE

Abstract

The effects of starch concentration on the rheological properties of dilute aqueous solutions of cassava starch were investigated. Cassava starch suspensions at different starch concentrations (0.2, 0.4, 0.6, 0.8, and 1.0 wt. %) were heated at 90 degrees C for 1 h and then rapidly cooled to 25 degrees C. The apparent viscosities of starch solutions were measured as a function of starch concentration. The cassava starch solution with a concentration of 0.2% showed Newtonian behavior, and as the concentration was increased beyond 0.4%, the solutions showed shear-thinning behavior. The flow behavior (apparent viscosity against shear rate) of the solutions was well described using a power law model. The consistency indices increased and the flow behavior indices decreased with the increasing of starch concentration. After storing the solutions at 25 degrees C for 24 h, precipitation of starch took place instead of gelation. The volume of precipitation bed increased linearly with starch concentration. (c) 2008 Elsevier Ltd. All rights reserved.