Dynamic viscoelastic properties of sweet potato studied by dynamic mechanical analyzer


Li Q., Lİ D., Wang L., ÖZKAN N., Mao Z.

CARBOHYDRATE POLYMERS, vol.79, no.3, pp.520-525, 2010 (Peer-Reviewed Journal) identifier identifier

  • Publication Type: Article / Article
  • Volume: 79 Issue: 3
  • Publication Date: 2010
  • Doi Number: 10.1016/j.carbpol.2009.08.035
  • Journal Name: CARBOHYDRATE POLYMERS
  • Journal Indexes: Science Citation Index Expanded, Scopus
  • Page Numbers: pp.520-525
  • Keywords: Sweet potato, Viscoelastic property, Dynamic mechanical analysis, GLASS-TRANSITION, DEFORMATION, BEHAVIOR

Abstract

The relaxation, creep, temperature-dependence and frequency-dependence characteristics of sweet potato roots were evaluated using a dynamic mechanical analyzer (DMA). The sweet potato was cut into rectangular to meet the testing requirements and wrapped with sealing film or aluminum foil to prevent water loss. The temperature scanning tests were carried out at 2 degrees C/min and 10 degrees C/min in the temperature range of 30-100 degrees C, and the frequency sweep tests were conducted in a range of 50-0.1 Hz. The regression results suggested that 5-element Maxwell model described relaxation behavior better for consisting of two relaxation times; the creep behavior matched the Burgers model well, and changes in creep parameters were observed after each creep cycle. The temperature scanning tests revealed that starch gelatinization was only obtained when the temperature increased at 2 degrees C/min. A resonance frequency was detected both in 3-point bending and compression deforming clamps. (C) 2009 Elsevier Ltd. All rights reserved.