Submitted to: Food Hydrocolloids Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: September 11, 2002
Publication Date: October 1, 2003
Citation: Carriere, C.J., Inglett, G.E. 2003. Constitutive analysis of the nonlinear viscoelastic properties of cellulosic fiber gels produced from corn or oat hulls. Food Hydrocolloids Journal. 17(5):605-614. Interpretive Summary: With the depressed prices for many agricultural materials today, the introduction of agricultural products into new markets and applications is essential to growth of the industry. In addition, the expansion of present market applications is also a viable vehicle to increase utilization of depressed agricultural commodities. In order to introduce these materials into new applications a detailed understanding of the performance of these bio-based materials needs to be obtained. The effective production of new, application-targeted materials in a cost-effective manner requires an understanding of the flow and processing behavior of the materials to be developed. This work presents some of the initial research at characterizing the flow behavior of ARS-patented cellulosic fiber gels known as Z-Trim, which have numerous uses in the food industry. Models for the flow behavior have been developed and evaluated. These models can be used in optimizing processing conditions to reduce production costs and predicting the performance of these materials in future applications. The work is continuing with more complicated bio-based blends.
Technical Abstract: The evaluation and development of validated models for the nonlinear viscoelastic (VE) behavior of materials is an important area of research, which has impact on a number of industrial processes including those in the food industry. Various nonlinear VE models have been developed over the years and evaluated for petroleum-based polymers; however, our understanding of the nonlinear VE behavior of biopolymers of industrial import lags our understanding of synthetic polymers. In the work reported herein, the nonlinear VE behavior of several cellulosic fiber gels prepared from either corn or oat hulls were investigated. The rheological properties were measured using a Rheometrics Series IV controlled-strain rheometer equipped with a cone and plate fixture. The measurements were conducted at 23 ± 0.1 ºC. The rheological data were interpreted using a strain separable K-BKZ type (Wagner) model with a damping function evaluated from stress relaxation data. The Wagner model was found to provide an accurate description of the rheological behavior of the suspensions.