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.

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: 1991

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references (leaves 109-115). Also available via the Internet.

Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xv, 176 p.; also includes graphics (some col.) Includes bibliographical references (p. 169-176). Available online via OhioLINK's ETD Center

Thesis (Ph. D.)--Michigan State University. Dept. of Economics, 1969. / Includes bibliographical references (leaves 243-257).

Thesis (Ph. D.)--University of Wisconsin--Madison, 1968. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 58-62).

Thesis (Ph. D.)--University of Wisconsin--Madison, 1968. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

The relationships between headspace gases in canned apple sauce and storage time and temperature, food pH and consistency, and headspace vacuum and volume were studied. The apple sauce processing method used essentially duplicated commercial procedures. Canned apple sauce was stored at l00°F for 7 or 10 months, and sampled for headspace gases with a modified Zahm air tester. Procedures were developed for sampling for chromatographic analysis gas from cans with high vacuum and small headspace, and for calculating gas volumes. A minimum headspaoe hydrogen was observed in samples within the pH range 3.45-3.75, in products of consistency within the range common to the Virginia commercial apple sauce, and in cans with higher vacuum. Maximum carbon dioxide content was noted in samples having a pH value of 3.45. Samples with more fluid consistency had more headspaoe carbon dioxide than those of higher consistency. Variations in headspaoe carbon dioxide content occurred in direct proportion to headspace size, and trends could not be associated with can vacuum. Oxygen was generally 1.2-1.9 percent of the headspace gas. Carbon monoxide was present in all samples in very small amounts. / Master of Science

The effect of processing water quality, specifically calcium and magnesium salt content (0-500 mg/1) and the addition of chelating agents (0- 250 mg/ 1 of aminopolycarboxylic acids, polyphosphates, hydroxycarboxylic acids or phytates), upon physico-chemical and organoleptic characteristics of canned Jonathan and Delicious apple slices, Montmorency cherries and Blue Lake green beans was investigated. Physical determinations: shear values, turbidity of syrup or brine measured via light transmittance, Hunter color and color difference meter readings and internal can corrosion; chemical composition: pectin as calcium pectate, volatile reducing substances, total acidity, pigment determinations, nitrate-nitrogen values; and sensory measurements: texture, shape, flavor, aroma, color value and uniformity of product and color value and turbidity of product brine or syrup were ascertained. Analyses of variance, Duncan's multiple mean comparison range tests and correlation or coefficients were calculated when appropriate. Use of hard water (300 mg/1) as a processing medium for canned apple slices and sour cherries decreased color and flavor acceptability but increased firmness and shear values. Excessive hardness toughened cherry epidermis making texture undesirable. Addition of 250 mg/1 CaNa2EDTA to Delicious apple slices canned in water containing 300 mg/1 salts improved color and flavor while firmness was retained. Delicious apple slices were firmer, and higher shear, nitrate-nitrogen and aroma scores and caused less detinning than Jonathan samples in all storage groups. As corrosion increased, nitrate-nitrogen, shear, firmness, flavor, aroma, and pigment values decreased. Color acceptability, reflectance, flavor and volatile reducing substance were higher and redness lower for Jonathan apple slices than Delicious samples stored at 35 and 75 F for 1 and 3 months, respectively, but not necessarily for samples stored at 100 F for 4 months. EDTA was ineffective in maintaining or improving Jonathan apple or Montmorency cherry quality, probably due ot the acidity of these cultivars. Apple and cherry quality decreased as storage temperature and duration increased from 35, 75 to 100 F for 1, 3 and 4 or 5 months, respectively, for all samples except Delicious apple slices with CaNa2EDTA. EDTA did provide most color protection in sour cherries, and citric acid, best flavor and aroma scores, while commercial and tap water processed sour cherries showed most deterioration, but none were of acceptable commercial quality after 5 month storage at 100 F. When comparing 1 month storage at 35 F with 3 months at 75 F, analyses of variance showed significant differences for every cherry characteristic measured except texture judged subjectively. All F values for apple storage variables were significant. Blue Lake green beans canned using distilled water or with 250 mg/ 1 CaNa2EDTA had higher color and greenness values, less turbidity, generally better flavor and aroma, but lower shear, shape and firmness scores than tap or hard water or commercially processed green beans. Addition of 250 mg/1 ascorbic acid to hard water used to process green beans retained greenness, clarity of brine, flavor and aroma while reducing slough and splitting of pods, when stored 4 months at 75 F.