Abstract
An extrusion attachment for the Lee-Kramer shear press is described. With this instrument some rheological properties of lard, margarine and shortening were measured. These included extrusion pressure and specific work of extrusion. By variation of extrusion speed and size of orifice a variety of rates of deformation could be obtained. When the rate of deformation was plotted against the specific work of extrusion, curves were obtained which were nearly straight beyond deformation rates of about 1 sec−1. The tangent to these curves represents the apparent viscosity. By measurement of the hardness before and after extrusion the work softening resulting from the extrusion could be measured. Some possible uses of the technique are discussed.
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Vasic, I., deMan, J.M. Measurement of some rheological properties of plastic fats with an extrusion modification of the shear press. J Am Oil Chem Soc 44, 225–228 (1967). https://doi.org/10.1007/BF02639262
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DOI: https://doi.org/10.1007/BF02639262