Submitted to: International Conference on Composites Engineering Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: August 14, 2004
Publication Date: August 14, 2004
Citation: Inglett, G.E., Lee, S. 2004. Rheological properties of biopolymeric composites of cellulosic and beta-glucan hydrocolloidal gels [abstract]. International Conference on Composites Engineering. p.291. Technical Abstract: The biopolymers from cellulose and beta-glucan hydrocolloidal have found wide utility and acceptance in the food industries as individual polymeric materials. Research studies are underway to look at the composite compositions for increasing their utilizations in industrial as well as food applications. The cellulosic biopolymer of this study was prepared from maize hulls by chemically and physically altering the pericarp cellular structures in a two stage operation requiring elevated temperatures and intense shear force. The dried gel products are readily dispersible in water and can be rehydrated to give high viscosity gels generally using vigorous high shear procedures, such as colloid mills and homogenization (Inglett and Carriere 2001). The viscosity increased from 9.4 +/- 0.9Pa-s to 12.6 +/- 1.1 Pa-s when the shear time was extended from 2.5 min to 10 min at 25 deg C. A colloid mill (Premier MillTM Model 90 with a high viscosity head) was used for achieving sufficient shear. Repeating the same experiment using 50 deg C water indicated only a modest increase in viscosity from 9.5 +/- 0.9 Pa-s to 10.7 +/- 1.1 Pa-s. There was little change in the hydration capacities, both staying between 24 and 26. The untreated maize bran did not demonstrate either the viscosity (around 4 +/- 0.4 mPa-s) or the hydration capacity of the maize fiber called Ztrim. The beta-glucan hydrocolloids (also called Oatrim) were discovered in 1988 and became a commercial product (Inglett 1991). Oatrim forms a fat-like gel that has one calorie per gram compared with nine calories per gram for fat and has heat stability for food applications. In addition to substituting for fat in foods, Oatrim's soluble beta-glucan contributes a hypocholesterolemic property. The Food and Drug Administration has allowed rolled oats, oat flour and oat bran to claim health benefits, provided that they are used to give at least 3 grams of soluble beta-glucan [(1-3)(1-4)-beta-D-glucan] per day as a part of a low-saturated fat, low-cholesterol diet.