The phase behaviour, flow behaviour, and interfacial properties of protein-polysaccharide aqueous two-phase systems with sugar

Pörtsch, Asja (2012). The phase behaviour, flow behaviour, and interfacial properties of protein-polysaccharide aqueous two-phase systems with sugar. University of Birmingham. Ph.D.

[img]
Preview
Portsch12PhD.pdf
PDF

Download (4MB)

Abstract

The aim of this work is to better understand the structuring processes in low fat dairy emulsions. Model sodium caseinate-galactomannan aqueous two-phase systems (NaCAS-GM ATPS) differing in GM-type (locust bean gum (LBG), tara gum (TG), guar gum (GG), fenugreek gum (FG)) and added sugar (trehalose, sucrose, glucose and fructose) were studied by the phase-volume ratio method, rheooptics, and droplet retraction method on phase equilibria, flow behaviour and interfacial properties, respectively, at pH 5.8 and 20°C.
The results revealed that the presence of sugar in concentrations 5-40 wt% resulted in an increase in cosolubility of the phases and a decrease in interfacial tension (σ). Sugar concentrations > 40 wt% decreased cosolubility. Based on the mannose:galactose ratio of GM and type of sugar (added in concentration 15 wt%) the best cosolubility and corresponding smallest σ was attributed to FG and trehalose, respectively. The flow of ATPS depended on quiescent microstructure, the shear and physical properties of the phases. In polysaccharide-continuous ATPS, the occurrence of a shear-induced phase inversion event was observed for 0- 20 wt% sugar. A further increase in sugar concentration >20 wt% was found to suppress this phenomenon due decreased viscosity ratio and formation of thread like structures in flow.

Type of Work: Thesis (Doctorates > Ph.D.)
Award Type: Doctorates > Ph.D.
Supervisor(s):
Supervisor(s)EmailORCID
Norton, IanUNSPECIFIEDUNSPECIFIED
Cox, Philip WilliamUNSPECIFIEDUNSPECIFIED
Licence:
College/Faculty: Colleges (2008 onwards) > College of Engineering & Physical Sciences
School or Department: School of Chemical Engineering
Funders: None/not applicable
Subjects: T Technology > TP Chemical technology
URI: http://etheses.bham.ac.uk/id/eprint/3528

Actions

Request a Correction Request a Correction
View Item View Item

Downloads

Downloads per month over past year