Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 20 of 20

Full-Text Articles in Life Sciences

Perceptions Of Current Club Managers Regarding College Coursework Necessary For Preparation For A Career As A Club Manager, Candice E. Clemenz Dec 1993

Perceptions Of Current Club Managers Regarding College Coursework Necessary For Preparation For A Career As A Club Manager, Candice E. Clemenz

Masters Theses

The purpose of this research was to gather and interpret the perceptions of current club managers regarding the college coursework that they believed was necessary to prepare a student for a career as a club manager. First, a list of course areas was developed via a review of hospitality curriculums, and conversations with industry professionals. The list was used to design Part 1 of a questionnaire that featured 13 course areas with corresponding descriptive and ascending levels of competencies. Instructions clearly directed club managers to select the highest level of competency for each course area that they thought should be ...


Formation Of Polycyclic Aromatic Hydrocarbons On The Surfaces Of Ultra-High Temperature Treated Meat, Michelle T. Foote May 1993

Formation Of Polycyclic Aromatic Hydrocarbons On The Surfaces Of Ultra-High Temperature Treated Meat, Michelle T. Foote

All Graduate Theses and Dissertations

The effect of ultra-high temperature (UHT) on production of polycyclic aromatic hydrocarbons (PAHs) on the surface of beef steaks was determined. Beef steaks were treated with five treatments, raw, UHT, UHT/grill marks, UHT/grill marks/microwave, and charcoal grilled. Four PAHs, benzo[a]pyrene, benz[a]anthracene, benzo[b]fluoranthene, and benzo[k]fluoranthene, were quantified. High performance liquid chromatography (HPLC) and gas chromatography (GC) were used to purify and analyze the PAH extracts, respectively. Levels of PAH found on charcoal-grilled steaks were higher than those observed in the literature. A balanced incomplete block design was used to analyze ...


Anaerobic Treatment Of Whey Permeate Using Upflow Sludge Blanket Bioreactors, Seokhwan Hwang May 1993

Anaerobic Treatment Of Whey Permeate Using Upflow Sludge Blanket Bioreactors, Seokhwan Hwang

All Graduate Theses and Dissertations

Whey permeate was anaerobically digested in laboratory scale upflow anaerobic sludge blanket reactors. Nine hydraulic retention times between 5 and 0.2 days were examined with a fixed influent concentration of 10.6 ± 0.2 g COD/L.

Chemical oxygen demand removal efficiency ranged from 99.0 to 18.9% and maximum production rate of methane gas was 2.67 L/L/day at a hydraulic loading rate of 12.97 kg COD/m3/day. About 70% of the chemical oxygen demand removed was converted to methane.

Both the nonlinear least square method with 95% confidence interval and linear ...


A Study Of Factors Controlling Physical Properties Of Mozzarella Cheese And The Manufacture Of A Reduced Fat Mozzarella Cheese, Richard Kevin Merrill May 1993

A Study Of Factors Controlling Physical Properties Of Mozzarella Cheese And The Manufacture Of A Reduced Fat Mozzarella Cheese, Richard Kevin Merrill

All Graduate Theses and Dissertations

Variables affecting the physical properties of Mozzarella cheese were investigated. The effects of various milk-clotting enzymes were examined. The type of milk coagulating enzyme used played a significant role in determining physical properties of direct acid Mozzarella cheese. Cook color was not affected by enzyme type, but melt and stretch were significantly affected.

Proteolytic nature of starter cultures was reviewed and recommendation s were give n. Cheese made with proteinase-deficient strains had more stretch after holding for 14 and 28 d than cheese made with non-deficient strains. Cheese made with pairs or single strains of L. helveticus had the same ...


Sensory And Functional Properties Of Wheat Stored Under Home Conditions, Marilyn M. Shumway May 1993

Sensory And Functional Properties Of Wheat Stored Under Home Conditions, Marilyn M. Shumway

All Graduate Theses and Dissertations

Samples of wheat that had been stored in homes up to 48 years were collected with information about age and storage conditions. Germination, weight per bushel, protein, moisture, grade, and aroma were investigated. Volumes of gluten balls and bread made from ground whole wheat samples were measured. Sensory attributes of bread were evaluated by Quantitative Descriptive Analysis (QDA) for eight flavor and seven texture characteristics. Because of the tremendous variation in samples, generalizations on cause and effect are difficult to make. No one criterion was a perfect indicator of quality. A high percentage of germination was one of the better ...


Hydrothermal Processing Of Soy Protein Products , Chunyang Wang Jan 1993

Hydrothermal Processing Of Soy Protein Products , Chunyang Wang

Retrospective Theses and Dissertations

Hydrothermal Cooking (HTC) is a steam infusion process used to continuously cook slurries at high temperatures for short periods of time. The objectives of present studies were to investigate the effects of HTC processing on functional properties of soy protein products and to contribute to a better understanding of protein ultrastructure changes induced by heat;In the first study, the effects of HTC processing on the functional properties of soy flour, soy protein concentrate (aqueous-alcohol-washed) and soy protein isolate were studied. HTC processing increased the NSI of soy protein concentrate by approximately four times (from 15 to 56%). HTC changed ...


Demand For Risky Foods And Food Safety , Kung-Cheng Lin Jan 1993

Demand For Risky Foods And Food Safety , Kung-Cheng Lin

Retrospective Theses and Dissertations

A demand for risky food model is constructed to study several aspects of food safety problems. On the basis of this proposed model, results are addressed in the following. First, when the food safety is exogenously fixed, an increase in the safety level of the risky food X[subscript]1 increases the demand for X[subscript]1 if X[subscript]1 is normal. However, when both goods are risky, a rise in the safety level of one good generally has an ambiguous effect on the demands. For the case where the safety level is endogenously chosen, the consumer will in ...


Granular Cold-Water-Soluble Starch: Preparation, Characterization, And Its Use On Controlled Release Of Atrazine , Jen-Fang Chen Jan 1993

Granular Cold-Water-Soluble Starch: Preparation, Characterization, And Its Use On Controlled Release Of Atrazine , Jen-Fang Chen

Retrospective Theses and Dissertations

Granular cold-water-soluble (GCWS) starches were prepared by alcoholic-alkaline treatments. The method was carried out by treating starches with mixtures of ethanol and alkali, primarily NaOH solution (3M), to swell starch granules. The treated starches were then neutralized with HCl (3M, in 100% alcohol), washed with aqueous alcohol solution, and dried in an oven at 80°C for 3 h. The method was effective to wide varieties of starches, including high amylose starches, normal starches, and waxy starches. The efficacy of the method depended mainly on concentrations of NaOH and ethanol, and reaction temperature. Different reaction conditions gave products different properties ...


The Use Of Real-Time Ultrasound Measurements To Predict Composition And Estimate Genetic Parameters Of Carcass Traits In Live Beef Cattle , David Albert Duello Jan 1993

The Use Of Real-Time Ultrasound Measurements To Predict Composition And Estimate Genetic Parameters Of Carcass Traits In Live Beef Cattle , David Albert Duello

Retrospective Theses and Dissertations

Both steers (n = 497) and bulls (n = 247) were ultrasonically (RTU) measured for 12-13th rib subcutaneous fat thickness (UFAT) and longissimus muscle area (ULMA) just previous to slaughter. Carcass measurements collected by experienced evaluators were used as a basis to determine the accuracy of ultrasound measurements. Mean differences between carcass and ultrasound measurements suggest that carcass fat thickness (CFAT) was slightly underestimated (.032 cm) and carcass longissimus muscle area (CLMA) was overestimated by 1.47 cm[superscript]2 with RTU. The mean absolute value of the difference between CFAT and UFAT was.227 cm while this mean absolute difference was ...


Effects Of Glycinin, B-Conglycinin, Their Subunits And Storage Conditions On Tofu Sensory Characteristics , Hui-Ping Chen Jan 1993

Effects Of Glycinin, B-Conglycinin, Their Subunits And Storage Conditions On Tofu Sensory Characteristics , Hui-Ping Chen

Retrospective Theses and Dissertations

Seven varieties of soybeans were selected: Vinton 81, LS 201, A8926, Pioneer 9202, NK 2026, NK 2303, and Latham 650. Vinton 81, LS 201, and Pioneer 9202 are commonly used for human foods and other varieties are usually used for oil production;The seven soybean varieties were different in their proximate chemical compositions and soy protein subunit composition. Glycinin subunits (A[subscript]3, A[subscript]4, A[subscript]1aA[subscript]1bA[subscript]2) were significantly different (p < 0.05) among varieties. The A[subscript]4 peptide was present in Vinton 81 and LS 201. The textural characteristics of tofu made from these varieties showed significant differences (p < 0.05). The relative amount of [alpha][superscript]' was negatively correlated (p < 0.05) with fracturability (r = 0.788). The glycinin/[beta]-conglycinin ratios (R) were correlated with hardness (r = 0.900) and fracturability (r = 0.901) of tofu among food beans;Soybean quality changed during storage (35°C and 84% relative humidity for 110 days). The nitrogen solubility index (NSI) decreased linearly (p < 0.05) over the storage periods for most varieties. The rate of decline of NSI was significantly correlated (p < 0.05) with the decrease in fracturability (r = 0.947) and cohesiveness (r = 0.857) of tofus made from stored Vinton 81 beans. The NSI value significantly correlated with cohesiveness (r = 0.812) of tofus made from stored Pioneer 9202 beans. The moisture decreased slightly over storage time. The extractable lipid content decreased linearly (p < 0.05) with time. The relative amounts of glycinin and [beta]-conglycinin decreased linearly with storage time for several varieties. The total buffer-extractable protein did not change significantly over time for all varieties. The relative amounts of subunits in seeds did change with storage time. The extractable A[subscript]4 peptide disappeared after 22 days of storage. The measured textural characteristics of tofu were significantly (p < 0.05) different with respect to time for all varieties except NK 2026. The Hunter colorimeter a value showed significantly (p < 0.05) change with time. The tofu color score, texture, and flavor preference scores obtained by sensory evaluation significantly (p < 0.05) changed with time for most varieties. Sensory evaluation hardness correlated (p < 0.05) with Instron hardness for A8926, cohesiveness for Pioneer 9202 and Vinton 81. For all varieties, except NK 2303, sensory evaluation color score correlated (p < 0.05) with the Hunter colorimeter a-value.


Factors Influencing The Sensory Quality Of Boneless Pork Loin Chops , Dawn Marie Canon Jan 1993

Factors Influencing The Sensory Quality Of Boneless Pork Loin Chops , Dawn Marie Canon

Retrospective Theses and Dissertations

Fresh loin chops from the tenth, eleventh and twelfth ribs were removed from 754 pigs entered in the National Pork Producers 1990 Genetic Evaluation Test (Phase 1), 629 pigs entered in the Fall, 1991 National Barrow Show (Phase 2), and 512 pigs entered in the Spring, 1992 National Barrow Show (Phase 3). Pigs from the Genetic Evaluation Test represented 13 breeds of sire and originated from 13 different states. Pigs from the National Barrow Show represented 8 breeds of sire. Loin chops (longissimus muscle) were removed from the bone and trimmed of external fat. Raw samples were analyzed for total ...


Evaluation For Food Packaging Potential And Environmental Compatibility Of Novel Degradable Starch-Polyethylene Plastics , Meera Kim Jan 1993

Evaluation For Food Packaging Potential And Environmental Compatibility Of Novel Degradable Starch-Polyethylene Plastics , Meera Kim

Retrospective Theses and Dissertations

Linear low-density polyethylene films were prepared that contained native corn starch (7, 14, or 28%), low- or high-molecular weight oxidized- polyethylene (15%) and a pro-oxidant mixture (manganese 55 ppm and vegetable oil). Each plastic blend was first mixed in a twin-screw extruder at 195°C, pelletized, then cast into films using a single-screw extruder at 205°C. Oxidized-polyethylene addition to starch-polyethylene films did not impair transparency and thickness of the films, and relatively small reductions in film mechanical properties were observed;Thermal and photodegradation properties of each film were evaluated by 70°C forced-air oven treatment (20 days), by high-temperature ...


Antibacterial Mechanism Of Phosphates In Staphylococcus Aureus , Ruby Muk-Lan Lee Jan 1993

Antibacterial Mechanism Of Phosphates In Staphylococcus Aureus , Ruby Muk-Lan Lee

Retrospective Theses and Dissertations

The minimum inhibitory concentrations (MIC) of phosphates (0.1% sodium ultraphosphate, UP; 0.1% sodium polyphosphate glassy, SPG; 0.5% sodium acid pyrophosphate, SAPP; 0.5% sodium tripolyphosphate, STPP; and 0.5% tetrasodium pyrophosphate, TSPP) were bactericidal to early exponential phase cells of Staphylococcus aureus ISP40 8325 in a pH 6 modified complete defined synthetic medium. Concentration effects were observed for each phosphate in which the higher the concentration, the greater the inhibition. Chain-length effects were observed for those phosphates in which the longer the chain-length, the greater the inhibition. Leakage of intracellular nucleotides were confirmed spectrophotometrically (release of A ...


Rapidly Measured Predictors For The Dry Milling Performance Of Corn, Nicholas Keith Fradgley Jan 1993

Rapidly Measured Predictors For The Dry Milling Performance Of Corn, Nicholas Keith Fradgley

Retrospective Theses and Dissertations

No abstract provided.


A Field Portable Ultrasound System For Bovine Tissue Characterization , Kyle Harold Holland Jan 1993

A Field Portable Ultrasound System For Bovine Tissue Characterization , Kyle Harold Holland

Retrospective Theses and Dissertations

Efforts by beef producers and beef packers to reduce carcass losses and to move the industry to a value-based marketing system have renewed their interest in the development of new electronic grading techniques for assessing beef carcass composition. A custom ultrasonic data acquisition system has been developed for the purpose of investigating the feasibility of beef tissue characterization. The unit developed is a compact, hand-held, six channel battery-operated data logger capable of sampling A-mode ultrasound signals at a rate of 15 megasamples per second. A custom epoxy encapsulated ultrasound transducer array was developed to fit the inner curvature of the ...


Site-Directed Mutagenesis To Enhance Thermostability Of Aspergillus Awamori Glucoamylase Expressed In Saccharomyces Cerevisiae , Hsiu-Mei Chen Jan 1993

Site-Directed Mutagenesis To Enhance Thermostability Of Aspergillus Awamori Glucoamylase Expressed In Saccharomyces Cerevisiae , Hsiu-Mei Chen

Retrospective Theses and Dissertations

A program of site-directed mutagenesis was undertaken to enhance thermostability of Aspergillus awamori glucoamylase. Nine mutations were designed, based on three different irreversible thermoinactivation mechanisms of glucoamylase. Each mutant was expressed in Saccharomyces cerevisiae, and their production, activities, and irreversible thermoinactivation rates were determined;First, the Asn182 and Asn395 residues were each replaced with Gln to reduce their deamidation rates. Asn395, but not Asn182, was N-glycosylated by yeast. Deletion of the N-glycan linked to Asn395 did not affect specific activity, but greatly decreased enzyme secretion and thermostability. Replacement of Asn182 by Gln did not change glucoamylase specific activity or thermostability ...


Charged Fusions For Enhanced Protein Purification And Immobilization By Ion-Exchange , Meng Hong Heng Jan 1993

Charged Fusions For Enhanced Protein Purification And Immobilization By Ion-Exchange , Meng Hong Heng

Retrospective Theses and Dissertations

This work was undertaken to investigate the enhanced binding of genetically engineered [beta]-galactosidase fusions in ion-exchange. The fusions used had a series of polyaspartate tails of the form: Gly-Asp-Pro-Met-Ala-(Asp)[subscript] n-Tyr fused to the carboxyl termini of the wild type [beta]-galactosidase (BGWT). The resulting fusions carried additional 1, 5, 11, and 16 negative charges and are designated as BGCD1, BGCD5, BGCD11, and BGCD16, respectively;The use of charged fusions for selective protein recovery was studied using hollow fiber ion-exchange membranes. The added tails allowed selective binding and release of [beta]-galactosidase in active form from Escherichia coli ...


Effects Of Usda Quality Grade And Heating On Palatability, Cholesterol Content, Fatty Acid And Proximate Composition Of Beef Strip Loin Steaks , Robert Dean Johnson Jan 1993

Effects Of Usda Quality Grade And Heating On Palatability, Cholesterol Content, Fatty Acid And Proximate Composition Of Beef Strip Loin Steaks , Robert Dean Johnson

Retrospective Theses and Dissertations

The objectives of this investigation were to determine the influence that broiler temperature and degree of doneness had upon palatability, cholesterol content (CC), and fatty acid (FA) and proximate composition (PC) of beef strip loin steaks from different USDA quality grades. Seven strip loins were obtained from each of USDA Standard, low Select, high Select, low Choice, ave to high Choice, and low to ave Prime quality carcasses of known age, ancestry and management. After storing 9 days (d) postmortem (PM), 3.0 cm steaks were cut (except Prime = 23 d), vacuum-packaged and frozen. After thawing, steaks were broiled at ...


Acceptor Reactions And Mechanism Of Leuconostoc Mesenteroides B-512fm Dextransucrase , Aziz Tanriseven Jan 1993

Acceptor Reactions And Mechanism Of Leuconostoc Mesenteroides B-512fm Dextransucrase , Aziz Tanriseven

Retrospective Theses and Dissertations

Although Hanes-Woolf plot showed that methyl [alpha]-D-glucopyranoside was an apparent competitive inhibitor for dextransucrase, a Michaelis-Menten plot using methyl [alpha]-D-glucopyranoside in the presence of high concentration of sucrose showed that it was not a real competitive inhibitor. We have also found that methyl 6-deoxy-[alpha]-D-glucopyranoside and methyl 6-deoxy-6-fluoro-[alpha]-D-glucopyranoside were weak inhibitors, whereas the corresponding sucrose analogues 6-deoxysucrose and 6-deoxy-6-fluorosucrose are very potent inhibitors for dextransucrase. From these findings, it is concluded that the acceptor, methyl [alpha]-D-glucopyranoside, does not compete with sucrose for the sucrose binding-sites and it binds at a separate acceptor binding-site;A ...


Lipid Oxidation In Dry Corn Masa Flour And Strategies To Improve Shelf-Life , Reyna Luz Vidal-Quintanar Jan 1993

Lipid Oxidation In Dry Corn Masa Flour And Strategies To Improve Shelf-Life , Reyna Luz Vidal-Quintanar

Retrospective Theses and Dissertations

Corn tortillas are one of the main corn products consumed in Mexico and Latin American countries. Dry corn masa flour has better shelf-life than wet corn masa, and is convenient and easy to use at commercial and home levels. The objectives of the present studies were to determine the extent of lipid oxidation in dry corn masa flours as sold in the retail market, to determine the shelf-life of dry corn masa subjected to different temperatures, and to determine the effects of corn lipids and germ proteins on dough properties and sensory characteristics of corn tortillas;In the first study ...