TitleEngineering nanostructured functional thin films for frozen foods application
NameGezgin, Zafer (author), HUANG, QINGRONG (chair), Ludescher, Richard D (internal member), Lee, Tung-Ching (internal member), King, Alan H (outside member), Rutgers University, Graduate School - New Brunswick,
Food industry and trade,
Frozen foods industry,
DescriptionNano-foods are becoming more common with the implementation of nanotechnological methods to the production, processing & packaging of foods. Food nanotechnology is bringing a new dimension to product development, by allowing the transfer of functionalities from biological molecules observed in nature to foods. Aim of this study is to transfer the ability of extracellular ice nucleators (ECINs) to trigger ice formation at higher sub-zero temperatures to a food packaging material, by creating a nano-thin ECIN layer on it. Earlier studies indicated shorter freezing times, higher ice nucleation temperatures and quality improvement when ECINs were mixed into foods. It is hypothesized that this effect can be retained with the nano-thin ECIN films. Our objective is to (1) investigate the biopolymer systems suitable for building food grade multilayers, (2) use these multilayers to immobilize ECINs, and (3) evaluate the ice nucleation activity of these films. Surface morphology of nano-thin films was investigated by atomic force microscopy (AFM), and the surface hydrophobicity was studied by the water contact angle measurements. Layer thicknesses were determined using the quartz crystal microbalance with dissipation monitoring (QCM-D) technique. A refrigerated water/ethylene glycol bath was used to study the ice nucleation activity of nano-thin layers. Chitosan, ε-polylysine, carrageenan and pectin were good alternatives to synthetic polyelectrolytes in multilayer formation. Parameter that affected the nanoscale properties of these biogenic multilayer systems were the molecular weight, molecular conformation, charge density and degree of esterification. An average of 1.8°C increase in ice nucleation temperatures and 5.5 minutes decrease in freezing times was observed with high purity deionized water samples frozen in ECIN coated LDPE films. Films retained their activity for up to 50 freeze-thaw cycles. This dissertation establishes a proof of concept for the application of the LbL deposition technique to engineer functional food grade nano-thin films. Preliminary experiments using our films to freeze milk, fish actomyosin and 20% sucrose solution resulted in shorter freezing times, better quality retention and ice nucleation at higher temperatures versus untreated control films. Implementation of this technology in frozen food packaging applications can actualize the significant energy-saving and quality-improvement potentials of nano-thin ECIN films.
NoteIncludes bibliographical references
Noteby Zafer Gezgin
CollectionGraduate School - New Brunswick Electronic Theses and Dissertations
Organization NameRutgers, The State University of New Jersey
RightsThe author owns the copyright to this work.