No description available.

No description available.

Heat transfer in canned particulate system in Newtonian and non-Newtonian liquids was studied during end-over-end agitation thermal processing in a pilot scale rotary retort. Computational methods for conventional overall heat transfer coefficient (U) and fluid to particle heat transfer coefficient (hfp) were found unsuitable in high viscosity fluids. A methodology for evaluating an apparent heat transfer coefficient (hap) between retort medium and particle, and an apparent overall heat transfer coefficient Ua between retort medium and can fluid was proposed. Use of h ap and Ua concepts permitted direct predictions of particle temperature and lethality based on retort temperature. / An L-16 orthogonal experimental design of experiments was carried out to select system factors that significantly affected hap and U a values for particles in high viscosity non-Newtonian and Newtonian fluids. Experiments using central composite rotatable design and full factorial design were carried out to study the effects of selected significant factors on hap and Ua. / Using all data obtained, dimensionless correlations were developed for the prediction of hap and Ua values. The developed correlations showed a good agreement with the experimental data. More precise predictions were achieved with trained artificial neural network (ANN) models. The results of ANN models could be compiled using algebraic equations and were included so that hap and Ua values could be predicted without actually using the ANN software. A flow visualization study was conducted to better understand the heat transfer behavior in high viscosity fluids. Results showed that in particulate high viscosity fluids, the particle liquid relative movement was very weak, implying that the heat transfer between them could converge to conduction-conduction rather than convection-conduction, which results in erroneous and unusually large hfp values.

There is no abstract available for this thesis.

The purpose of this study was to determine the phenolic constituents of Bartlett pears and to evaluate the processed samples for extent of discoloration and to relate the two. Pears were obtained from three orchards in the Medford area and from three orchards at each of the three elevations, 500, 1700, and 2300 feet, in the Hood River area. Four replications were made. Values for the total phenol content of the pears ranged from 54.3 to 120.8 milligrams per 100 grams of fresh pear tissue. The leuco-anthocyanin content of the pears ranged from 6.4 to 21.0 milligrams per 100 grams of pear tissue and the flavanol content ranged from 11.3 to 44.8 milligrams per 100 grams of pear tissue. The pH of the pears ranged from 3.70 to 4.09. Color of the pears processed for twenty-five, thirty-five and forty-five minutes was measured. Those pears with the highest concentration of total phenols, leuco-anthocyanin and flavanols and the lowest pH were the pinkest when overprocessed. Pears which were least pink were among the lowest in total phenols, leuco-anthocyanin and flavanols and had the highest pH values. However, among the remaining fruits, the pinker pears were not necessarily those with the higher total phenolic content or the lower pH values. / Graduation date: 1963

Graduation date: 1940

Graduation date: 1954

Graduation date: 1953

Graduation date: 1942

Graduation date: 1991