This dissertation discusses, in brief, the production and transport property characterization of films made from the extrusion and biaxial stretching of [beta] nucleated isotactic polypropylene and the extrusion of PEBAX block copolymers. Multilayered films for modified atmosphere packaging applications were also produced by coextrusion and biaxial stretching of these two materials and similarly characterized. Current membranes for packaging applications are generally produced by coating a porous support with a polymeric solution to deposit an active layer for separation. The goal of this project is to displace membranes produced by solvent-based processes, which are environmentally hazardous and thus costly, with equivalent or superior materials produced using melt extrusion. / text

The effects of microbial growth, packaging film permeability, and freezing on the discoloration of beef was assessed by measuring myoglobin derivatives and specifically the rate of formation of metmyoglobin on the surface of Longissimus dorsi and Semimembranosus bovine muscles during 12 days of storage at 2°C. Frozen thawed sterile beef samples experienced higher metmyoglobin formation than fresh sterile beef samples. By day 2, up to 20% metmyoglobin was formed in the thawed samples whereas, the fresh samples reached this value after day 6. After 6 days, the growth of Pseudomonas florescence had a significant effect on myoglobin oxidation and this behavior continued for the remaining period of the storage. Gas barrier film and gas permeable film exhibited similar results at day 0 and day 3 of storage, however at day 6 of storage, samples packaged with the gas barrier film showed metmyoglobin percentage significantly higher that those packaged with gas permeable film. (Abstract shortened by UMI.)

The advent of smart and wearable systems along with their Internet of Things (IoT) applications are driving unparalleled product miniaturization and multifunctional integration with computing, wireless communications, wireless healthcare, security, banking, entertainment, and navigation and others. This evolution is primarily enabled by the integration of multiple technologies such as RF, analog, digital, MEMS, sensors and optics in the same system. Integration of these heterogeneous technologies creates a new need for multiple power supply rails to provide device-specific voltage and current levels. Hence, multiple power converters, each requiring several passive components, are used to create stable power-supplies. However, state-of-art power supplies employ SMD passives that are relatively large, forcing these modules to be placed on the board far from the active IC. This leads to significantly sub-par frequency performance and poses a challenge for ultra-miniaturized and reliable power supplies. Hence, novel packaging technologies that can improve miniaturization, electrical performance and reliability at a relatively low-cost are required to address these challenges. Georgia Tech-PRC proposes 3D integration of passives and actives (3D IPAC) as doubleside thin components on ultra-thin glass substrates with through-package-vias (TPVs) to meet these requirements. This thesis focuses on a comprehensive methodology to demonstrate a 3D IPAC power module, starting with modeling, design, fabrication and characterization to validate 3D integrated ultra-thin inductors and capacitors in ultra-thin substrates. Another key focus of this thesis is to advance building block technologies such as thinfilm inductors and capacitors to achieve the target properties for 3D IPAC integration. As a first building block technology, advanced capacitor technologies were explored with high-k thinfilm barium strontium titanate dielectrics and lanthanum nickel oxide electrodes as an alternative to Cu, Ni and Pt electrodes for improved performance and cost. The BST capacitors with LNO electrodes resulted in a capacitance density of 20-30 nF/cm2 with leakage as low as nA/nF up to 3 V. A glass-compatible process was developed with crystallization temperatures less than 650 C. These capacitors with thinfilm electrodes and dielectrics can be integrated into ultra-thin interposers and packages. This can help improve the capacitor performance up to the GHz range. As a next build block, Si-nanowires were studied as high surface area electrodes for high-density capacitors. Analytical modeling was performed to understand the length of the nanowires based on the catalyst size. This modeling study was then extended to understand the cut-off frequency of the capacitors based on the RC time constant. The wires were fabricated using both chemical vapor deposition (CVD) and wet-etch processes. However, it was noticed that the wet-etch process provided more control on the geometry, density and orientation of the nanowires. Si-oxide was thermally grown on the surface of the wires. A capacitance density of 200 nF/mm2 was achieved. It was noticed that the cut-off frequency of such capacitors was limited to the lower kHz range. However, the operating frequency can be improved by simply using a highly conductive Si-substrate. The second part of the thesis focuses on inductor and capacitor integration on ultra-thin glass substrates for high-frequency power modules using the 3D IPAC approach. Analytical models were used to calculate the required passive component values based on the target frequency, ripple currents and voltages of the power module. Next, a SPICE model was used to optimize the value of the required passives based on the output parasitics. The L and C structures were then modeled using 2.5D method of moments (MOM) approach. The modeling results showed 7-8 X improvement in Q-factor when the structures were fabricated using the 3D IPAC approach relative to those fabricated on the same side of the substrate. A fabrication process flow was designed based on through-via and doubleside metallization with semi-additive patterning (SAP). The components were fabricated as thinfilms on either sides of the substrate and interconnected with through-vias. The LC network was characterized using a two-port vector network analyzer. The results showed low-pass filter response, which matched the design targets of cut-off frequencies upto 100 MHz. This study, therefore, demonstrates advanced thinfilm component technologies for ultra-high frequency power-supply. It also presents, for the first time, a 3D integrated passives and actives (3D IPAC) approach with integrated L and C for power modules.

Not available / text

The combined effect of Modified Atmosphere Packaging (MAP) involving gas packaging, oxygen absorbent and other environmental factors to control aflatoxin production by Aspergillus flavus and Aspergillus parasiticus in both synthetic media and peanuts were studied using a process optimization technique termed Response Surface Methodology (RSM). Regression analysis of the data indicated that water activity (a$ sb{ rm w}$), pH, storage temperature, initial concentration of headspace oxygen and inoculum level were all highly significant factors (p 0%). These changes in the barrier characteristics influenced the headspace gas composition within the product and under modified atmospheres hence the level of aflatoxin detected in these stored products. / In conclusion, this study has shown that the combined effect of several "barriers" can be used in conjunction with low oxygen modified atmosphere and high barrier packaging films to inhibit or reduce aflatoxin to safe and acceptable levels, particularly at abusive temperatures encountered during storage.

No description available.

No description available.

Listeria monocytogenes is a pathogenic, psychrotrophic microorganism that is ubiquitous in nature. L. monocytogenes has been isolated from numerous meat products, both fresh and processed, the incidence of contamination varying greatly. The ability of Listeria to grow in meats depends on temperature, pH, water activity (a$ sb{ rm w}$), nutrients, species and numbers of competing microorganisms, gaseous conditions, and levels of additional barriers. Therefore, methods to control the growth of L.monocytogenes are of great importance to food processors since this organism can grow under a wide range of environmental and storage conditions. Two methods of control, in conjunction with temperature, were studied in this project: (i) modified atmosphere packaging (MAP) and (ii) chitosan, to determine the optimum levels of these "hurdles" needed to effectively control the outgrowth of L.monocytogenes in both model broth and agar systems and in fresh pork loin. On the basis of these preliminary studies, a combination of chitosan as a dipping solution and modified atmosphere packaging were investigated to control the growth of L.monocytogenes in fresh pork loin. Pork loin samples were dipped in a 0.2% chitosan solution for 60 seconds and packaged under various atmospheres in Cryovac bags and stored at 5, 10 and 15$ sp circ$C up to 28 days. Samples were monitored for physical, chemical and microbiological changes throughout the storage period. Optimum control over the growth of L. monocytogenes was achieved using a combination of 100%N$ sb2$ + an Ageless FX oxygen absorbent and dipping in a 0.2% chitosan solution. Based on these studies, a combination of 0.2% chitosan and MAP could be used to extend the shelf life of pork without adversely affecting color, odor and exudate loss while inhibiting the growth of the pathogenic microorganism, L.monocytogenes. (Abstract shortened by UMI.)

This research investigates consumers' preferences and attitudes towards the packaging of FMCG (Fast Moving Consumer Goods) products and the influence that this packaging has on their buying habits and purchasing decisions. Respondents' likes, dislikes as well as key purchase drivers were examined. Focus groups were held to gauge the respondent's attitudes and perceptions towards packaging as well as their expectations of what it should be like. The researcher employed a descriptive research design method using qualitative methods to analyse the data collected. A total of twenty five focus groups were held, with twelve women in each group (ie 300 respondents). Respondents consisted of females residing in the Bedfordview, Sandton, Yeoville and Melville areas in Gauteng. One-hour focus groups were held during July, August and September 2003. / Thesis (MBA)-University of Natal, Durban, 2003.

The exact nature of the point of sale can vary considerably, from huge hypermarkets to roadside stalls and cafes. At each of these, the consumer is faced with a dizzy array of products to choose from. In all of these instances, packaging can provide the trigger for differentiating the product and hence to purchase it. In the Fast Moving Consumer Goods industry, almost 70% of the purchase decision are taken at the point of sale. Effective packaging at the point of sale can render huge opportunities for a company, as this can allow the product to stand out against competitors, evoking emotions from the consumer to purchase their product. Unilever is the second largest consumer goods company in the world. Predominate product categories include the food and home care businesses. In South Africa they dominate the laundry market with well-known brands such as OMO, Skip, Sunlight, Surf etc. As part of their growth strategy, much focus is placed on harmonisation of product and packaging development. Apart from aligning product formulations, this strategy also includes aligning pack designs. It is therefore critical that before any decision is made on changing pack designs to conform to global standards, that an in-depth study be undertaken in order to assess how changes in packaging elements affect the South African consumer. It is also important that all involved in the local packaging value chain, ie artwork agencies, packaging suppliers, company brand development members, are in tune with what the local consumers want. The objective of this research is to establish which (combination of) packaging elements (ie colour, shape, materials and design) in laundry products are most effective in influencing consumers purchasing decision. The study focussed specifically on Surf LSM 7-8 consumers in Durban. The research further looked at which packaging elements associated with the Surf brand influence purchase decision as perceived by members of the packaging value chain (artwork agencies, packaging suppliers and company's brand development) and compared this to findings in the consumer segment. This was done to evaluate how effective the packaging value chain is in delivering an effective package to the target consumer. The research was carried out as follows: 1. A literature review to gather knowledge about packaging elements and its communicating capability of messages in order to identify which elements have these capabilities. 2. A quantitative study to gain insight into which attributes of packaging elements are most effective in communicating specific product attributes associated with the Surf platform. 3. A semi-quantitative study to gain insight into which attributes of packaging elements are effective in influencing a consumers purchasing decision It was found that respondents from brand development had a good understanding of Surf consumers' current image of the brand. Artwork agencies and packaging suppliers need to become more involved with consumer research and immersions in order to bridge the gap in better understanding what the brand stands for. The colour blue still remains the main visual cue linked to the Surf brand. There could be an opportunity for the colour red to be used effectively in order to depict brightness. There is also a possibility that flexible packaging would be more appealing provided that opening/closing could be improved. Holographic designs should definitely be incorporated onto a Surf pack. / Thesis (MBA)-University of Natal, Durban, 2003.