Rheological Differences of Waxy Barley Flour Dispersions Mixed with Various Gums

Abstract

Rheological properties of waxy barley flour (WBF) dispersions mixed with various gums (carboxyl methyl celluleose, guar gum, gum arabic, konjac gum, locust bean gum, tara gum, and xanthan gum) at different gum concentrations were examined in steady and dynamic shear. WBF-gum mixture samples showed a clear trend of shear-thinning behavior and had a non-Newtonian nature with yield stress. Rheological tests indicated that the flow and dynamic rheological parameter (apparent viscosity, consistency index, yield stress, storage modulus, and loss modulus) values of WBF dispersions mixed with gums, except for gum arabic, were significantly higher than those of WBF with no gum, and also increased with an increase in gum concentration. In particular, konjac gum at 0.6% among other gums showed the highest rheological parameter values. Tan δ values of WBF-xanthan gum mixtures were lower than those of other gums, showing that there is a more pronounced synergistic effect on the elastic properties of WBF in the presence of xanthan gum. Such synergistic effect was hypothesized by considering thermodynamic compatibility between xanthan gum and WBF. These rheological results suggest that in the WBF-gum mixture systems, the addition of gums modified the flow and viscoelastic properties of WBF, and that these modifications were dependent on the type of gum and gum concentration.

Effect of Tara Gum Addition on Steady and Dynamic Shear Rheological Properties of Rice Starch Isolated from the Korean Rice Variety ‘Boramchan’

“…The G″ values of RS+TG samples were remarkably increased compared to the values of G′ of RS pastes, resulting in the increase of tan δ values of RS+TG pastes. This result was similar to Lee et al ( 19 ) and Kim and Yoo ( 20 ). Lee et al ( 19 ) reported that both G″ and tan δ values of rice starch were increased in the presence of TG.…”

“…Furthermore, the K and η a,500 of all RS+TG pastes were significantly higher than those of RS with increasing amounts of TG. Similar findings were observed by Kim and Yoo ( 20 ). They observed that the addition of TG to waxy barley flour dispersions had a significant increase in the K and η a,100 values of waxy barley flour dispersions.…”

“…Lee et al ( 19 ) reported that both G″ and tan δ values of rice starch were increased in the presence of TG. Furthermore, Kim and Yoo ( 20 ) observed that adding galactomannans such as TG and LBG elevated the viscous properties of waxy barley flour.…”

Influence of honey types and heating treatment on the rheological properties of glutinous rice flour gels

“…Beakers were heated in a water bath (Memmert, Schwabach, Germany) at 60°C for 5 min to pre-gelatinise the GRF dispersions with manual stirring every 15 s, to prevent sedimentation of flour that causes a separation and leads to formation of two layers. Then, they were transferred to a shaking thermostatic water bath (WB22-16X2501, Memmert, Schwabach, Germany) at 95°C for 30 min with a mild agitation (Chun and Yoo 2004;Kim and Yoo 2017) provided by water bath shaker to minimize settling of flour particle. Gelatinisation that occurs during cooking allows leaching of amylopectin from starch granules for enzymatic hydrolysis due to high susceptibility of gelatinised starch to enzymatic action (Holm et al 1988;Thomas and Atwell 1997).…”