title: Effect of sodium chloride on the glass transition of condensed starch systems.
abstract: The present investigation deals with the structural properties of condensed potato starch-sodium chloride systems undergoing a thermally induced glass transition. Sample preparation included hot pressing at 120°C for 7 min to produce extensive starch gelatinisation. Materials covered a range of moisture contents from 3.6% to 18.8%, which corresponded to relative humidity values of 11% and 75%. Salt addition was up to 6.0% in formulations. Instrumental work was carried out with dynamic mechanical analysis in tension, modulated differential scanning calorimetry, Fourier transform infrared spectroscopy, scanning electron microscopy and wide angle X-ray diffraction. Experimental conditions ensured the development of amorphous matrices that exhibited thermally reversible glassy consistency. Both moisture content and addition of sodium chloride affected the mechanical strength and glass transition temperature of polymeric systems. Sodium ions interact with chemical moieties of the polysaccharide chain to alter considerably structural properties, as compared to the starch-water matrix.
authors: School of Applied Sciences, RMIT University, City Campus, Melbourne, Vic 3001, Australia.
authors: Lillian
authors: L
authors: Chuang
authors: School of Applied Sciences, RMIT University, City Campus, Melbourne, Vic 3001, Australia.
authors: Naksit
authors: N
authors: Panyoyai
authors: School of Applied Sciences, RMIT University, City Campus, Melbourne, Vic 3001, Australia.
authors: Robert
authors: R
authors: Shanks
authors: School of Applied Sciences, RMIT University, City Campus, Melbourne, Vic 3001, Australia. Electronic address: stefan.kasapis@rmit.edu.au.
authors: Stefan
authors: S
authors: Kasapis
mesh_terms: D006358:Hot Temperature; D012965:Sodium Chloride / Q000737:chemistry*; D011198:Solanum tuberosum / Q000737:chemistry; D013055:Spectrophotometry, Infrared; D013213:Starch / Q000737:chemistry*; D044366:Transition Temperature; D014867:Water / Q000737:chemistry
chemical_list: D014867:Water; D012965:Sodium Chloride; D013213:Starch
keywords: Glass transition; High-solid systems; Sodium chloride; Starch