title: Oscillatory and steady shear rheology of gellan/dextran blends.
abstract: Oscillatory and steady shear rheology of gellan (G) and dextran (D) solution individually, and in blends (G/D ratio 1:1, 1:2, and 1:3 w/v) with a total hydrocolloid concentration of 3 % (w/v) were studied at 25 °C. Individually, 1.5 % dextran and 1.5 % gellan in solution exhibited Newtonian and non-Newtonian behavior, respectively. A blend of equal proportion of dextran and gellan (G/D = 1:1) exhibits a distinct gel point (G' = G″), and further addition of dextran in the blend (G/D = 1:2 and 1:3) resulted predominating liquid-like (G″ > G') behavior. A plot of G' vs G″ distinctly showed the gradual transition of the blend. Shear stress (τ)-shear rate ([Formula: see text]) data fitted well the Herschel-Bulkley model. The G/D blend exhibited shear thinning behavior with flow behavior index less than unity. The Cox-Merz rule did not fit well for the complex shear viscosity (η*) and apparent viscosity (η) of the blend.
authors.affiliation: Halal Products Research Institute, Universiti Putra Malaysia, Putra Infoport, 43400 Serdang, Selangor Darul Ehsan Malaysia.
authors.forename: Nurul Hawa
authors.initials: NH
authors.lastname: Ahmad
authors.affiliation: Food & Nutrition Program, Kuwait Institute for Scientific Research, P.O Box 24885, 13109 Safat, Kuwait.
authors.forename: Jasim
authors.initials: J
authors.lastname: Ahmed
authors.affiliation: Halal Products Research Institute, Universiti Putra Malaysia, Putra Infoport, 43400 Serdang, Selangor Darul Ehsan Malaysia ; Faculty of Food Science and Technology, Universiti Putra Malaysia, 43400 Serdang, Selangor Darul Ehsan Malaysia.
authors.forename: Dzulkifly M
authors.initials: DM
authors.lastname: Hashim
authors.affiliation: Faculty of Food Science and Technology, Universiti Putra Malaysia, 43400 Serdang, Selangor Darul Ehsan Malaysia.
authors.forename: Yazid Abdul
authors.initials: YA
authors.lastname: Manap
authors.affiliation: Halal Products Research Institute, Universiti Putra Malaysia, Putra Infoport, 43400 Serdang, Selangor Darul Ehsan Malaysia ; Bioprocessing and Biomanufacturing Research Centre, Faculty of Biotechnology and Biomolecular Science, Universiti Putra Malaysia, 43400 Serdang, Selangor Darul Ehsan Malaysia.
authors.forename: Shuhaimi
authors.initials: S
authors.lastname: Mustafa
keywords: Complex viscosity; Cox–Merz rule; Dextran; Gellan; Herschel-Bulkley; Oscillatory rheology