DYNAMIC VISCOELASTICITY AND STRESS-RELAXATION IN STARCH PASTES

The dynamic viscoelasticity and stress relaxation often types of starc h pastes were measured. The dynamic moduli increased with increasing f requency, and were different for each starch paste, changes in tan del ta for cassava and potato starch pastes being about 0.5-0.6. The stres s relaxation behaviour of all the samples tested could be represented by a four-element mechanical model. The relationship between spinnabil ity and stress relaxation was determined, the spinning distance increa sing with increased relaxation time (tau(2)) No satisfactory linear re lationship between spinning distance and relaxation time (tau(2)) was apparent with the 10 starch paste samples.