Effect of instantaneous high pressure on rheological properties of dietary fiber suspension from soybean residue.

摘要

Soybean (Glycine max) residue, a byproduct from soy milk and tofu production, is considered as a source of dietary fiber. Dietary fiber is obtained from soybean residue by enzyme-chemical method and processed with instantaneous high pressure (IHP) at 40, 100 and 140 MPa, for 1-6 treatment times. Rheological characteristics of all fiber samples were determined by Brookfield DV III+ Rheometer. Results were analyzed and discussed with the tests of controlled rate ramp, up-down rate ramp, time sensitivity, temperature sensitivity and dynamic yield. Power Law model and Bingham model were used to fit the non-IHP and IHP processed samples. The fitting confidence (CoF) of Power Law model ranged from 0.9153 to 0.9947, and the CoF of Bingham model ranged from 0.9250 to 0.9910; the dynamic yield stresses were 3.914 and 54.781 dyne/cm2 for non-IHP (40 MPa) and IHP (140 MPa) processed samples, respectively. Results showed that IHP treatment could increase the apparent viscosity and dynamic yield stress of fiber suspension. The IHP processed sample had higher material model CoF compared to non-IHP processed sample, and the CoF of Power Law and Bhingham model increased from 0.9843 to 0.9947 and 0.9833 to 0.9910, respectively, after processing the sample with IHP at 140 MPa.