Date of Award
Doctor of Philosophy
Engineering and Applied Sciences
Alexandra Pekarovicova, Ph.D.
Hussam Khasawaneh, Ph.D.
James Springstead, Ph.D.
Food packaging, glucomannan, mathematical modeling, rheology, synthesis of biofilms, xylan
Scientists are most concerned about the need for green alternatives for efficient food packaging polymers to replace petroleum-based packaging products. The waste of corn cobs and the roots of the konjac plant contain hemicellulose, xylan and glucomannan respectively, and can be used to produce biofilms for food packaging.
The aim of these studies is to formulate biofilms from glucomannan-xylan blends that compete with petroleum-based plastic wrap. The biofilms must be strong, smooth, transparent, have a water vapor barrier, have the required mechanical properties and be cheap. Biofilms from glucomannan were stiff, lacked mechanical properties, and absorbed moisture. Therefore, it reacts with other polymers to enhance its properties. When glucomannan reacted with nanofibrillated cellulose, the mechanical properties were improved. The viscosity of the fluid was lowered by reacting with xylan, enhancing the wettability of the biofilms. Crosslinking is a tartaric acid process used to limit moisture absorption by biofilms, allowing food to survive longer without spoiling. Printing on the surface was tested by a flexographic proofer. The rheological studies of the filmogenic solutions that will become biofilms were investigated. The viscosity, loss, and storage moduli of the solutions were measured using a rheometer. The viscosity was described using the cross-model for non-Newtonian fluids, and the Maxwell model was utilized to explain the time-dependent behavior of polymers subjected to shear stress. The storage and loss moduli, as well as viscosity, agreed perfectly with the models. When the cast biofilms were tested for moisture absorption resistance, they performed well. These experiments reveal that glucomannan-xylan, generated from agricultural waste, is a suitable replacement for plastic wrap.
Al-Ajlouni, Kholoud, "Synthesis of Glucomannan-Xylan Composite Biofilms: Characterization and Applications for Food Packaging" (2023). Dissertations. 4021.