Influence of gliadins on rheology of methylcellulose in 70% (v/v) aqueous ethanol

TEMPO-oxidized cellulose fibers from wheat straw: Effect of ultrasonic pretreatment and concentration on structure and rheological properties of suspensions

Cellulose and TEMPO-oxidized cellulose fibers (TOCF) from the wheat straw were prepared with ultrasonic and chemical treatments to investigate structure and functionalities. Sol-gel transition of TOCF suspensions has been investigated using rheology to unveil the roles of ultrasonic pretreatment and temperature at various concentration. It was found that TOCF extracted with or without ultrasonic pretreatment exhibit similar functional groups in FTIR. However, different crystal structures and thermal stabilities were revealed in XRD and TGA, respectively. The gelation was independent of the ultrasonic pretreatment, while the rheological properties were highly infuenced by the concentration and temperature of the TOCF suspensions. TOCF suspensions presented a strain thinning behavior in large amplitude oscillatory shear tests. Lissajous curves showed that the elastoplastic behavior was predominantly modulated by the fiber concentration and strain amplitude other than the ultrasonic pretreatment. These results could improve the understanding of the relationships between TOCF structure and rheological properties.

Dynamic rheological properties of native and cross-linked gliadin proteins

A comparison of cross-linked and native gliadin suspensions, with respect to the state of protein globular structure was carried out using small-angle X-ray scattering (SAXS), dynamic light scattering (DLS) and rheological analysis. Gliadin suspensions were also analyzed in the presence and absence of glycerol. DLS analysis showed that R(h) increased only with gliadin/EDC/NHS suspensions. However, Kratky plots revealed that gliadin and gliadin/L-cysteine maintained their globular shape even in absence or presence of glycerol. Rheological experiments revealed that gliadin and gliadin/L-cysteine suspension exhibited a similar profile with three main domains, and a sol-gel transition. Gliadin/EDC/NHS did not present any sol-gel transition, and this fact corroborates with DLS results and the hypothesis of lower protein-protein interaction, which are in agreement with G″ > G'.

Can dietary fibre help provide safer food products for sufferers of gluten intolerance? A well-established biophysical probe may help towards providing an answer

Gluten intolerance is a condition which affects an increasing percentage of the world's population and for which the only current treatment is a restrictive gluten free diet. However could the inclusion of a particular polysaccharide, or blends of different types, help with the provision of 'safer' foods for those individuals who suffer from this condition? We review the current knowledge on the prevalence, clinical symptoms and treatment of gluten intolerance, and the use and properties of the allergens responsible. We consider the potential for dietary fibre polysaccharides to sequester peptides that are responsible for activation of the disease in susceptible individuals, and consider the potential of co-sedimentation in the analytical ultracentrifuge as a molecular probe for finding interactions strong enough to be considered as useful.