RELATIONS BETWEEN AGGREGATIVE, VISCOELASTIC AND MOLECULAR-PROPERTIES IN GLUTEN FROM GENETIC-VARIANTS OF BREAD WHEAT

Glutens differing in their low- and high-molecular-weight glutenin sub units (LMW-GS and HMW-GS) were extracted from genetic variants of brea d wheat. Their composition was analysed by electrophoresis, the gluten in size distribution was determined by size-exclusion chromatography. Rheological measurements in the dynamic regime and electron spin reson ance spin-labelling experiments gave data on the viscoelasticity and t he protein flexibility of the glutens, respectively. In glutens differ ing in their HMW-GS, a relation is observed between the composition, a ggregative properties, segmental flexibility and viscoelastic behaviou r. This is not found in glutens with different LMW-GS. However, the pr oportion of rigid polypeptide segment is related to the height of the elastic plateau in all cases. The organisation of the protein network in gluten is discussed in reference to this data.