ABSTRACT
Rheology is the study of the deformation and ow behavior of matter. The term “rheology” and its denition were coined by Eugene C. Bingham and Markus Reiner in the late 1920s, and accepted when the American Society of Rheology was founded in 1929. “Panta rei-Everything ows,” credited to the Greek philosopher Heraklit of Ephesus (550-480 B.C.) or to one of his scholars, fathered the name of the discipline. Basically, all materials have rheological properties. Purely viscous uids and purely elastic solids limit the spectrum of possible material responses to applied stress or strain. The close correlation between rheological properties and microstructure of the materials makes the area relevant for many uids studied in polymer science, colloid and bio-science, cosmetics, geology, and in our case, in food science. The aim of rheological uid characterization is to quantify the functional relationships between a deformation and the resulting stresses acting in the rheometric ow either under steady or unsteady ow conditions.
