Gelatin vs Polysaccharide in Mixture with Sugar

Abstract

The structural behavior of a well-characterized gelatin sample has been revisited to investigate the morphology of its network in the presence of sugar. This was then contrasted with the corresponding properties of the gelling polysaccharides agarose, kappa-carrageenan, and deacylated gellan. Small deformation dynamic oscillation, differential scanning calorimetry in plain and modulated mode, visual observations, and transmission electron microscopy were used to identify the structural characteristics of the biopolymers from the rubbery plateau through the transition region to the glassy state. In contrast to the collapse of the polysaccharide gels at intermediate levels of co-solute, gelatin forms reinforced networks. The drop in polysaccharide network strength is accompanied by a decline in the enthalpy of the coil-to-helix transition, whereas the transition enthalpy is more pronounced in gelatin gels in accordance with their strengthening. Tangible evidence of the molecular transformations was obtained using microscopy, with polysaccharides disaggregating and dissolving in the saturated sugar environment. Gelatin, on the other hand, is visualized in an aggregated form thus producing a phase-separated topology with sugar.

Effect of gelatin on molecular mobility in amorphous sucrose detected by erythrosin B phosphorescence

“…The decrease in mobility at $0.01 wt ratio of gelatin and above is consistent with dynamic rheology studies of sugar/gelatin mixtures, [53][54][55][56] which indicate that addition of only 1 wt % polymer increases both the viscous and elastic moduli as well as the glass transition temperature of the sugar matrix. Our data suggest that addition of gelatin increases the temperature of the dynamic transition by perhaps as much as 15-20°C at high gelatin content.…”

“…Our data suggest that addition of gelatin increases the temperature of the dynamic transition by perhaps as much as 15-20°C at high gelatin content. Although we see no evidence for it in our results, it is also possible that the dynamic behavior at high wt ratios also reflects phase separation into sugar-rich and gelatin-rich domains as noted by Kasapis et al 55 Spectroscopic measurements appear to reflect not only the bulk effects of gelatin polymer on matrix dynamics at high wt ratios but also to monitor some more local and subtle effect on matrix dynamics at low wt ratios.…”

Tunable Gel Formation by Both Sonication and Thermal Processing in a Cholesterol‐Based Self‐Assembly System

“…[23] The rheological parameters of both the T-gel and the S-gel of 1 a indicate an enhanced solidlike character relative to the counterparts for 1 c; this is possibly because of the higher solubility of 1 c than that of 1 a in organic solvents. Meanwhile, the T-gel of 1 a (or 1 c) exhibited a larger G' value than the S-gel of 1 a (or 1 c), which indicates a denser packing of the 1 a (or 1 c) molecules in the T-gel.…”

Temperature and time effects on the structural properties of a non-aqueous ethyl cellulose topical drug delivery system

“…Both moduli have relatively low values at higher temperature (e.g., 5 • C), whereas there is an order-of-magnitude build up of viscoelasticity at the low temperature end (i.e., −25 • C). Data was then processed following the method of reduced variable otherwise known as the time-temperature superposition principle (TTS) (Ferry, 1991;Kasapis, Al-Marhoobi, Deszczynski, Mitchell, & Abeysekera, 2003).…”