Mechanism Underlying the Inactivation of E. coli by High Pressure Carbon Dioxide (HPCD)

A Haake rheometer was used to study the effect of glutamic acid(Glu) on the rheological properties of tapioca starch paste in the present work.The results obtained showed that both tapioca starch pastes with and without added Glu were pseudoplastic and thixotropic.Both the pseudoplasticity and thixotropy initially increased and then decreased with increasing amount of Glu addition.The apparent viscosity of tapioca starch paste decreased with increasing shearing speed as a shear thickening phenomenon.Both neat and Glu-added tapioca starch pastes showed a weak gel behavior,and both the storage modulus(G') and loss modulus(G'') first increased,then decreased,and finally tended to be Newtonian fluids with increasing amount of Glu addition.