Structure of maltodextrin gels ? a small angle X-ray scattering study

Abstract

Abstract:The structure of maltodextrin gels was investigated by small angle X-ray scattering. The inhomogeneities in the maltodextrin gels are molecular aggregates with maximum dimensions of almost 300 nm. Their shape can be approximated by oblate ellipsoids of revolution with an axial ratio of 0.1. The radius of gyration of the aggregates amounts to about 90 nm. For this reason in the nomenclature of Papkov the gels are polymer gels of the 2 na type. The melting of these aggregates is measured by SAXS with a position sensitive detector in the range near 56 ~

Study of cryostructuration of polymer systems. XXI. Cryotropic gel formation of the water–maltodextrin systems

“…Increasing the MD concentration in the solution up to 20 g/dL and higher resulted in gelation of the initially liquid systems after storing at positive temperature. This gelation behavior is to be expected from concentrated MD–water solutions 3, 17–19. Therefore, solutions containing MD of more than 15 g/dL were not, as mentioned above, considered here, since self‐association of MD into gels while still at positive temperatures could interfere with subsequent cryotropic gelation.…”

Blends of Maltodextrin and Other Polysaccharides as Binders of Aqueous α‐Alumina Suspensions for Ceramic Processing

“…As already stated in the introduction gelling of maltodextrins requires low temperatures (47C), an addition of amylose and a prolonged period of time [6][7][8][9][10][11][12][13][14]. Lowering the temperature of huge quantities of bulk alumina suspensions used by ceramic industry to 47C and long setting times, would lead to excessive rise of production costs.…”

“…Gelling of maltodextrins has been extensively studied and described in the past three decades. The structure of maltodextrin hydrogels was characterized by low-resolution NMR, water sorption isotherms, X-ray scattering (both small and wide angle), dynamic viscosity and differential scanning calorimetry [6][7][8][9][10][11][12][13][14]. In these studies maltodextrins gels were obtained in different conditions.…”

Molecular gelation mechanism of maltodextrins investigated by wide-angle X-ray scattering

“…In the nongelling systems crystalline structures cannot be detected. The crystalline domains consist of ordered double helices, aggregated into flat discs with a diameter of 280 nm and a height between 28 and 36 nm [6]. We can imagine the gelation process as follows.…”

“…We established the existence of lamellar domains with higher electron density in a thermally reversible maltodextrin gel by means of small-angle X-ray scattering investigations [6]. The measurements of the X-ray excess scattering of these domains in the wide-W 746 angle region, which we wish to report on in this paper, had the purpose of gaining an understanding of the intramolecular order and the intermolecular structure of the polysaccharide chains in the domains with higher electron density and to elucidate their relationship to the gel formation.…”