Bridging the Divide between the High- and Low-Solid Analyses in the Gelatin/κ-Carrageenan Mixture

Abstract

Over the past few years, a considerable amount of work has been done in several laboratories on the measurement of structural properties of low-solid biopolymer mixtures or high-solid materials of a single biopolymer in the presence of co-solute. The main objective of this work has been to establish a correlation between the two types of systems and extend it to a binary mixture in a high-solid environment. In doing so, it employed well-characterized kappa-carrageenan and gelatin samples in an aqueous preparation or in the presence of glucose syrup and sucrose. The phase behavior of the composite gel was ascertained using small-deformation dynamic oscillation, differential scanning calorimetry, and light microscopy. Experimental observations were built into polymer blending laws that argued for an explicit phase topology and distribution of solvent between the two networks. A working hypothesis was formulated and applied to high-solid mixtures thus identifying phase or state transitions in the time/temperature function. This led to the development of a mechanical glass transition temperature as the threshold of two distinct molecular processes governing the "rubber-to-glass" transformation. A stage was reached at which the predictions of the hypothesis were found to be in good agreement with the experimental development of viscoelasticity in the high-solid kappa-carrageenan/gelatin mixture ranging from the rubbery plateau and the transition region to the glassy state.

Effect of the extent of pasting on the dynamic rheological properties of acidified skim milk gels containing normal rice starch

“…Of particular relevance to the present study, the mechanical properties of composite biopolymer gels which are extensively investigated from theoretical and experimental view points (Clark, Richardson, Ross-Murphy, & Stubbs, 1983;Kasapis & Al-Marhoobi, 2005;Kasapis, Morris, Nortron, & Clark, 1993;Morris, 1992). More recently, Kontogiorgos, Ritzoulis, Biliaderis, and Kasapis (2006) investigated the rheological and structural properties of acid-set sodium caseinate gels containing b-glucan, and they showed that although the system phase separated, the rheology of the mixture is dominated by that of the protein network at low b-glucan concentrations (p3%).…”

Rheological investigation and molecular architecture of highly hydrated gluten networks at subzero temperatures

“…Non-invasive mechanical measurements have to be conducted within the linear viscoelastic region (LVR) of the material, where the magnitudes of stress and strain are related linearly (Kasapis, 2004;Kasapis and Al-Marhoobi, 2005;Kasapis, 2006). Fig.…”

Phase Behavior of the ι-Carrageenan/Maltodextrin/Water System at Different Potassium Chloride Concentrations and Temperatures

“…Segregative phase separation is driven by the Flory-Huggins interactions of polymer-polymer and polymer-solvent that are much more temperature dependent 35 , whereas associative phase separation usually originates from the relatively temperature-insensitive electrostatic interaction between polymers. Enhanced biopolymer compatibility at higher temperature is understandable, since the repulsive interactions 1 A "steeper" tie-line in the case of the pseudo-binary phase diagrams presented here actually corresponds to a less steep or more horizontal tie line in the true ternary phase diagram. between polymer neighbors tend to be weaker as temperature increases.…”

“…Considerable attention has been paid to the behavior of biopolymer mixtures due to their broad technological applications 1,2 . In the food industry, polysaccharide/polysaccharide and polysaccharide/protein mixtures are often used to control product properties and even to create "new" foods with desired texture and quality 3 .…”