Gelatin shear modulus

In spite of the above drawbacks. Equations 6.1 and 6.2 are popular mainly due to their simple form and have been used to estimate Me of protein (e.g., egg, gelatin) and other gels from shear modulus-concentration data (Table 6-2) (Fu, 1998). Its successful application to protein gels initially has been attributed to the greater flexibility of polypeptide chains in comparison to polysaccharide chains that are relatively stiff. In addition, the inability to employ low strain rates in early experimental studies on polysaccharide gels could be another reason. 

Clark, A. H., Evans, K. T., and Fairer, D. B. 1994. Shear modulus-temperature meltdown profiles of gelatin and pectin gels. Int. J. Bio. Macromol. 16 125-130. 

Despite the complexity of internal cell structure, which comprises the containing membrane, gelatinous interior cytoplasm, internal granular bodies, fibrous skeleton, and nuclei, each cell may be treated approximately as a spherical viscoelastic shell containing a viscous fluid. The model of an outer shell with an inner fluid describes very well the deformation of red blood cells and also of artificial vesicles made by sonicating phospholipids in water. The shell dictates the equilibrium while the fluid contents dictate the rate of approach to equilibrium, A red cell needs three numbers to describe its response time of 0.1 s an area compressibility k— 10 mNm , a shear modulus 10 Nm"", and a viscosity 10 Pa s. ... 

In order to get an idea of the values of Y ax. an example is given for a 5 wt% aqueous solution of gelatin with a weight average molecular weight of 70kg/mol in this case the equilibrium shear modulus at room temperature... 

To find out, if there is a correlation between the content of the network junctions and the helical content of the mixture, we have combined kinetic measurements of the mechanical and optical properties. For this reason we have constructed a special measuring cell for the simultaneous detection of the complex shear modulus and the optical rotation of polymer/solvent systems, e.g. gelatin/water up to 4 wt.% of gelatin. 

Takemesa, M Chiba, A. (2001). Gelatin mechanism of K and i-Carrageenan investigated by correlation between the strain-optical coefficient and the dynamic shear modulus. Macromolecules, Vol. 34, No. 21, pp. 7427-7434, ISSN 0024-9797. 

The results of investigation of the interfacial properties (thermodynamic and rheological) of the aqueous gelatin/ lecithin mixtures in the wide range of component ratios are presented in this work for the first time. It has been shown that adsorption of gelatin/lecithin complexes (formed in the bulk aqueous phase) at the immiscible liquid interface leads to self-assembly of the interfacial viscoelastic layer. The non-monotonic time-dependent interfacial shear viscosity and elastic modulus evolution were observed. This effect was explained by the phase transitions proceeding in time at the liquid interface in the systems containing lecithin. 

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