Rheopectic behavior of rendered fat

Waste fat is an integral part of the processing of animal by-products in rendering plants. The flow behavior and time-dependent flow properties of waste fat in the temperature range of 10ºC, 20ºC, 30ºC, and 62ºC was studied. Waste fat presented non-Newtonian behavior. Three mathematical models were used for prediction of the flow behavior of waste fat, including the Casson, Steiger-Ory, and Herschel-Bulkley models. The Herschel-Bulkley model sufficiently described the flow behavior of the waste fat at different temperatures. Several kinds of rheological curves were determinated for description of the flow behavior. Rheopectic behavior of rendered fat was determinated at temperatures lower than 30ºC.