Effect of high pressure on rheological characteristics of liquid egg

Whole liquid egg (WLE) and albumen have been denatured at high hydrostatic pressure (HHP). This paper deals with the effect of HHP on rheological characteristics of WLE, albumen, and yolk. The applied pressure ranged between 100 and 400 MPa for a residence time of 30 min. An advanced controlled stress rheometer was employed to study the rhological properties at a shear rate of 0-200 s(-1) using double concentric cylinder for WLE and albumen while parallel plate geometry was used for yolk with shear rate range of 0-500 s(-1). Both WLE and albumen behaved as time dependent fluids (thixotropic) however HHP reduced time dependency substantially. The protein coagulation at 300 MPa was supported by rheological measurement and native and sodium dodecyl sulfate electrophoresis. Albumen individually exhibited more pressure effect compared to WLE. Thixotropy of yolk varied significantly (P<0.05) during pressurization. (C) 2003 Swiss Society of Food Science and Technology. Published by Elsevier Science Ltd. All rights reserved.