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All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

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Reduction Of Sodium Nitrite And Sodium Chloride In A Cured Meat Product By Using Acid Development To Inhibit Botulinal Toxin Formation, Angsana Assamongkorn May 1985

Reduction Of Sodium Nitrite And Sodium Chloride In A Cured Meat Product By Using Acid Development To Inhibit Botulinal Toxin Formation, Angsana Assamongkorn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Pediococcus acidilactici as a lactic acid producer, and sucrose were added to breakfast strip products in order to reduce added levels of sodium nitrite and sodium chloride and yet limit the growth of Clostridium botulinum and inhibit toxin production. Sucrose at 0.4 or 0.9% with P. acidilactici at 1.0 x 108 cells/g were added during preparation of breakfast strip products prepared with combinations of 40 or 80 ppm sodium nitrite and 1.0 or 2.0% sodium chloride. Other ingredients were added at levels normally used in cured meat products. C. botulinum types A and B at 1,000 spores/g were inoculated …


Eeg And Evoked Potential Measured Of Age And Sex Differences In Central Nervous System Processing, Judith Ann La Marche May 1984

Eeg And Evoked Potential Measured Of Age And Sex Differences In Central Nervous System Processing, Judith Ann La Marche

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Age and gender differences in CNS information processing were investigated with EEG measures of power spectral analysis and cortical coupling, and evoked potential measures of brainstem auditory evoked potentials (BAEPs), visual evoked potentials (VEPs), pattern reversal evoked potentials (PREPs), and P300 evoked potentials. Eighty normal volunteers comprised four subgroups of 20 subjects: young females and young males (25-35 years); old females and old males (55-70 years).

Trends were generally consistent across evoked potential measures: women and young people produced faster latency responses; females and oldsters produced larger amplitude responses. Old age was associated with reduced variability of electrophysiological responding across …


Source Of Inoculum, Yield And Quality Of Tomato As Affected By Leveillula Taurica, Wayne B. Jones May 1984

Source Of Inoculum, Yield And Quality Of Tomato As Affected By Leveillula Taurica, Wayne B. Jones

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Tomato transplant stock from southern Nevada served as a source of inoculum and developed disease symptoms of tomato powdery mildew approximately three weeks before Utah-grown transplants. Plants from Nevada and Utah were equally infected seven weeks after planting and no differences in severity or yield were detected at the end of the season due to rapid spread of the fungus. Tomato yields were reduced ca 40% in check plots when compared to plots treated with triadimefon, propiconazol or sulfur. The amount of sunburned fruit in check plots was three to four times greater than in plots where the disease was …


Effects Of Diflubenzuron When Fed To Adult Female Alfalfa Weevils, Mohamed M. Middib May 1984

Effects Of Diflubenzuron When Fed To Adult Female Alfalfa Weevils, Mohamed M. Middib

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this project was to evaluate diflubenzuron ovicidal effects on adult female alfalfa weevils Hypera postica in the laboratory. There was little relationship of weevil mortality to dosage or length of exposure of the adult to the chemical. An indirect result of diflubenzuron was an increase in muscardine fungus (Beauveria Sp.). Other effects of the chemical on the adults were yellow deposits and tissue extending from the tip of the abdomen.

The main effect of dilfubenzuron when fed to female alfalfa weevils was on the eggs. The effects were dosage related, especially on eggs viability. The viability was …


Dynamics Of Arid-Land, Perennial Plant Populations With An Examination Of Potential Causal Agents, Henry George Gardiner May 1984

Dynamics Of Arid-Land, Perennial Plant Populations With An Examination Of Potential Causal Agents, Henry George Gardiner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rigorous statistical examination of the population dynamics of a number of long-lived perennial plant species permitted an interpretation of changes in those populations and the establishment of potentially important causal agents. Survival and recruitment of six species from the mulga-zone rangelands of Western Australia varied across three climatically different periods following the removal of domestic livestock.

Two species' populations (Eragrostis xerophila and Maireana glomerifolia) had their rates of increase reduced by kangaroo and euro grazing. Both survival and recruitment of Eragrostis xerophila were reduced by this grazing while Maireana glomerifolia suffered reduced recruitment during all periods. These negative …


Detailed Description And Nomenclature Of High Resolution G-Banded Horse Chromosomes And Cytogenetic Analysis Of Hereditary Multiple Exostosis In Horses, Alma Maciulis May 1984

Detailed Description And Nomenclature Of High Resolution G-Banded Horse Chromosomes And Cytogenetic Analysis Of Hereditary Multiple Exostosis In Horses, Alma Maciulis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A reliable technique for obtaining late prophase, prometaphase and greater numbers of metaphase chromosomes is presented. The increased number of mitoses and high resolution chromosomes were obtained using a modification of the typical three-day blood culture technique in which the cell cycle was temporarily blocked at the G1-s border with methotrexate. A high resolution G-band idiogram is presented using a system similar to the standardization of human chromosomes. The use of this technique and system of nomenclature will facilitate routine analyses of horse chromosomes and provide a basis for the identification and recording of chromosome aberrations in this …


Initial Assessment Of The Introduction Of Spottail Shiner (Notropis Hudsonius) And Delta Smelt (Hypomesus Transpacificus) Into Willard Bay Reservoir, Utah., Thomas E. Sommerfeldt May 1984

Initial Assessment Of The Introduction Of Spottail Shiner (Notropis Hudsonius) And Delta Smelt (Hypomesus Transpacificus) Into Willard Bay Reservoir, Utah., Thomas E. Sommerfeldt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Spottail shiner (Notropis hudsonius) and delta smelt (Hypomesus transpacificus) were introduced into Willard Reservoir to improve the forage base for walleye (Stizostedion vitreum vitreum) and black crappie (Pomoxis nigromaculatus). Spottail shiners were stocked in early spring in 1981, 1982, and 1983. Hauling mortality was generally great and an estimated 34,500 live fish were stocked in the 3-year period. Spottail shiner reproduction occurred each year of stocking. Delta smelt were introduced in 1982 with the stocking of 15,000 adult spawning fish. Stocking survival was estimated at 99%. Freshly spawned eggs were also obtained …


Comparisons Of Snow Deposition, Soil Temperature, Matric Potential And Quasi-Friction Velocity Between A Windward Site And A Lee Shelter In A Cold Desert, Harvey L. Neuber May 1984

Comparisons Of Snow Deposition, Soil Temperature, Matric Potential And Quasi-Friction Velocity Between A Windward Site And A Lee Shelter In A Cold Desert, Harvey L. Neuber

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Regimes of snow depth, soil temperature, soil matric potential and quasi-friction velocity in a windward site and a lee shelter were examined. The differences were analyzed from a biological perspective to characterize each location in terms of site favorability to plant growth. The chronology of wind and precipitation events was investigated.

Snow depth was measured with a system of stakes arranged around and in the interior of a rectangular plot encompassing both a windward site and a lee shelter. Soil temperature, soil matric potential and water potential were measured along a transect which originated in the windward site and terminated …


Seed Reserves In Stockpiled Topsoil On A Coal Mine Near Kemmerer, Wyoming, Cynthia K. Johnson May 1984

Seed Reserves In Stockpiled Topsoil On A Coal Mine Near Kemmerer, Wyoming, Cynthia K. Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objectives of this study were to determine how seed reserves varied with depth in topsoil stockpiles and to evaluate the effect of length of time of storage on the number of viable seeds and number of species of seeds.

Soil samples were taken from five topsoil piles representing zero to three years of storage on the Elkol-Sorenson mine near Kemmerer in southwestern Wyoming. Seeds were extracted using flotation/separation methods and were tested for viability using 2,3,5-triphenyl tetrazolium chloride solution. Data were analyzed using nonparametric statistical tests.

Overall density of seeds in topsoil piles was low. No relationship was found …


Forage Quality Comparison Of Burned And Nonburned Aspen Communities, Deborah L. Blank May 1984

Forage Quality Comparison Of Burned And Nonburned Aspen Communities, Deborah L. Blank

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objectives of this study were to assess the effects of prescribed burning on herbaceous and browse forage quality in the aspen forest type for elk and domestic sheep.

Plant samples of selected forage species were taken from burned and nonburned plots within three different prescribed burns in southeastern Idaho. These samples were analyzed for in vitro dry matter digestibility, crude protein, calcium and phosphorus. Data were analyzed using the analysis of variance.

There was little improvement in forage quality as a result of prescribed burning, with some reduction in quality in 1983 exhibited by pinegrass (Calamagrostis rubescens). …


A Look At Some Grandfather Intergenerational Relationships As Perceived By Their Adult Children, Leonard E. Stout May 1984

A Look At Some Grandfather Intergenerational Relationships As Perceived By Their Adult Children, Leonard E. Stout

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to investigate the quality of grandfather's relationships with his adult child and their oldest child. A questionnaire was used to obtain demographic data, determine some personality and interaction patterns that can be observed as the male adult develops in the parent and grandparent roles, and examine how specific variables affect grandfather relationships and behavior. Data were gathered from 165 Utah State University students and their spouses, of which over 75% belong to the Church of Jesus Christ of Latter-day Saints.

The results support good intergenerational relationships. Proximity of grandfather and extended family members was …


Resource Acquisition In The Presence Of A Novel Stimulus By Coyotes Of Different Social Rank, Warren E. Johnson May 1984

Resource Acquisition In The Presence Of A Novel Stimulus By Coyotes Of Different Social Rank, Warren E. Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study investigated the acquisition of food by hand-reared coyotes, Canis latrans, of different social rank in a familiar area with and without novel objects (safe and potentially unsafe conditions). The first objective was to test the hypothesis that dominant animals are more hesitant than subordinates in approaching food in the presence of a novel stimulus. The results were that dominant pups usually were the first to feed in the absence of novel stimulus, and subordinate pups were the first to feed when novel objects were present. The second objective was to see if the behavior of subordinates in …


The Effects Of A Commons Simulation And Fines On A Generalization Test, William Boyle May 1984

The Effects Of A Commons Simulation And Fines On A Generalization Test, William Boyle

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The present study investigated the effect of a commons simulation and fines on a generalization test that incorporated several features important in the real world. Two hundred and seventy-five volunteer college students in groups of seven participated in this study. Approximately one-half received exposure to the commons simulation and one-half did not. One-half of the groups in each treatment level received two posttests with a fine option available and the other one-half received two posttests without this option. The two posttests differed in that one was played with a large unknown referent group and the other was played with the …


Adolescent Identity Status In Current Familial Relationships During Separation, Eugene E. Campbell May 1984

Adolescent Identity Status In Current Familial Relationships During Separation, Eugene E. Campbell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

College students were assessed as to ego identity status and perceptions of their relationships with parents during their first year away from home. Each parent was also asked to rate the relationship. There was general agreement between parents and adolescents although the data indicate that mothers and adolescents share a more similar view of their relationship than did the fathers and adolescents.

The hypothesis that females would report more affection and communication with their parents than would males was partially supported. Daughters were more communicative with their mothers and were more affectionate toward both parents than were sons.

Several proposed …


Analysis Of Processes To Determine Site Suitability For A Marina At Bear Lake, Charles J. Houghten May 1984

Analysis Of Processes To Determine Site Suitability For A Marina At Bear Lake, Charles J. Houghten

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this thesis was to determine the criteria necessary for an analysis of site suitability for locating a marina at Bear Lake. Once criteria were defined and pertinent resource factors collected, a method to analyze the criteria was utilized to aid in the selection of the best site for locating this marina. Various methods to analyze site suitability were evaluated and the pros and cons of the chosen approach, a cluster analysis of existing resource transect data with hypothetical transect criteria, were discussed. Based on this study, no optimum sites were located at Bear Lake for a marina …


Photoaffinity Labeling Of The Antimycin Binding Site In Rhodopseudomonas Sphaeroides, Emily Wilson May 1984

Photoaffinity Labeling Of The Antimycin Binding Site In Rhodopseudomonas Sphaeroides, Emily Wilson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to identify the site of interaction of antimycin with the ubiquinone-cytochrome b-c1 oxidoreductase in the photosynthetic bacteria, Rhodopseudomonas sphaeroides. To accomplish this goal, three areas of research were undertaken: the synthesis of a radiolabeled, photoaffinity analog of antimycin, identification of the inhibitory characteristics of this analog, and the photoaffinity labeling of the antimycin binding site. All three areas were accomplished.

The major finding of this study was the identification of an 11,000 dalton polypeptide as the predominantly labeled protein. Although this polypeptide was not exclusively labeled, it was consistently labeled and showed competition …


Time Course Of Enzyme Catalyzed Reactions: The Stoichiometry A --> P + Q, Tamra Tuttle May 1984

Time Course Of Enzyme Catalyzed Reactions: The Stoichiometry A --> P + Q, Tamra Tuttle

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The feasibility of using an integrated rate equation to analyze the kinetics of a second-order, enzyme-catalyzed reaction has been investigated. The inducible arginine decarboxylase from Escherichia coli B. was chosen for this study because it catalyzes an irreversible reaction with stoichiometry A --> P + Q, the simplest second order case. Values for five of the eight possible kinetic constants were determined from 21 time courses. Of the remaining three, the uncompetitive product inhibition constant for CO2 was shown to be between 0 and 0.06, while the values of the competitive product inhibition for CO2 and the uncompetitive …


Range Beef Cattle Productivity In Southern Utah, Mouslim A. Maiga May 1984

Range Beef Cattle Productivity In Southern Utah, Mouslim A. Maiga

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Twenty-six range beef cattle ranches in southern Utah were surveyed by personal interview to obtain production data. The data were used to characterize the level of production efficiency in terms of calving rate, weaning rate, weaning weight, and net weaning weight in these operations; and to identify factors associated with differences in productivity.

The data revealed that productive efficiency was generally lower than the potential.

Mean calving rate of cows exposed for breeding was 83.4%. Stepwise regression involving calf death losses at or shortly after birth and heifer replacement rate accounted for 98.3% of the variance in calving rate. Calving …


Chemical Composition And Acceptability Of Rain Damaged, Field Dried Alfalfa Hay, Cesar Augusto Araque H. May 1984

Chemical Composition And Acceptability Of Rain Damaged, Field Dried Alfalfa Hay, Cesar Augusto Araque H.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Water was applied to swaths of cut alfalfa forage with oscillating sprinklers to stimulate rain damage to field drying alfalfa hay to determine the changes in chemical composition, loss of yield, and acceptability of rain damaged hay to sheep. An additional objective was to develop models to estimate yield losses form experimental hay. The experimental hay was prepared with a 2x2x4x4x2 factorial design. The factors were two different cuttings (July and September), two width of swath (3.05 m and 4.27 m), four times of applying artificial rain (3h, 8h, 13h, and 24h after cutting), four levels of artificial rain (no …


The Relationship Of Ewe Body Mass To Lamb Production, Sebhatu Gebrelul May 1984

The Relationship Of Ewe Body Mass To Lamb Production, Sebhatu Gebrelul

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Body size was estimated by multiplying the average of the hip and chest widths by body length and chest depth in 208 ewes of three genotypes: Targhee x Targhee (TXT), Finn x Targhee (FXT), and Suffolk x Targhee (SXT), and two seasons, fall (pre-breeding) and spring (post-lambing). The estimated ewe body size did not fluctuate with season, body condition or physiological stress and proved to be a constant measure of size. Measuring linear body dimension is time consuming; and hence ewe body size can best be approximated by the chest depth in a regression equation. In the absence of linear …


Combined Scale Weight, Height At Hips And Visual Condition Score As An Indicator Of Functional Body Size In Range Cows, Patricia B. Davis May 1984

Combined Scale Weight, Height At Hips And Visual Condition Score As An Indicator Of Functional Body Size In Range Cows, Patricia B. Davis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Thirty-five range cows of various breeds were obtained for the study. Body measurements taken were live weight and hip height and all cows were condition scored for level of fatness. The cows were slaughtered and the following morning several carcass measurements were taken and the plate was removed from the left side. These plates were boned and the remaining flesh ground for chemical analysis of percent carcass fat. Regression equations were calculated for estimating percent carcass fat from condition score, weight:height ratio and hip height (R2=.765). However, condition score alone is the single best estimator for percent carcass …


Influence Of Breed Type, Milk Production Potential And Cow Size Upon Maintenance Requirements, Jacqueline Lee Kennedy May 1984

Influence Of Breed Type, Milk Production Potential And Cow Size Upon Maintenance Requirements, Jacqueline Lee Kennedy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two biological types of cows, straightbred Herefords (HxH) and Simmental-Hereford crosses (SxH), of similar body condition were individually fed over a 10 week period to compare the biological types for maintenance and to determine the influence of milk production potential and of size. Cows were nonlactating and in the last part of the first trimester of pregnancy. During the first 5 weeks of the feeding experiment, one-half of each type was fed 75% of estimated maintenance while the other half was fed 125% of estimated maintenance. During the last 5 weeks of the experiment those fed at 75% of maintenance …


Natural Killer Cell Activity And Beta-Endorphin In The Mink (Mustela Vison) And The In Vitro Effect Of Beta-Endorphin In Immunologic Assays, Nancy Cathleen Pace May 1984

Natural Killer Cell Activity And Beta-Endorphin In The Mink (Mustela Vison) And The In Vitro Effect Of Beta-Endorphin In Immunologic Assays, Nancy Cathleen Pace

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to investigate natural killer cell activity and the possible role of beta- endorphin in a natural model of autoimmune orchitis, the dark mink.

An assay was developed to study natural killer cell activity in the mink and base-line levels of activity in this specie were determined. Natural killer cell activity was assessed in fertile mutation mink, primary infertile dark mink and secondary infertile Utah dark mink with autoimmune orchitis. The study included three sampling times: November, March and April. Natural killer cell activity was significantly lower in mink studied in April than it was …


Petrology Of The Middle Jurassic Twin Creek Limestone, Lincoln And Sublette Counties, Southwestern Wyoming, David R. Raubvogel May 1984

Petrology Of The Middle Jurassic Twin Creek Limestone, Lincoln And Sublette Counties, Southwestern Wyoming, David R. Raubvogel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Twin Creek Limestone of Middle Jurassic age was studied in the Tunp, Salt River, and Wyoming Ranges in southwestern Wyoming. Modern carbonate environments and their ancient analogs were compared with information obtained from field study and petrographic analysis of samples of the Twin Creek Limestone in order to delineate environments of deposition, paleogeography, and diagenetic history.

Six major lithofacies were recognized: (1) carbonate mudstone; (2) carbonate mudstone breccia; (3) fossiliferous wackestone; (4) packstone-grainstone; (5) terrigenous mudstone; and (6) sandstone. These lithofacies were deposited in a variety of environments, including outer shelf platforms (carbonate mudstone and fossiliferous wackestone), oolitic sand …


Effects Of Clearcutting On Forage Production, Quality And Decomposition In The Caatinga Woodland Of Northeast Brazil: Implications To Goat And Sheep Nutrition, Robert D. Kirmse May 1984

Effects Of Clearcutting On Forage Production, Quality And Decomposition In The Caatinga Woodland Of Northeast Brazil: Implications To Goat And Sheep Nutrition, Robert D. Kirmse

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Clearing of trees from the so-called caatinga woodland that characterizes the vegetation of the semi-arid region of northeast Brazil offers possibilities for increasing forage production. This research analyzed the first-year effects of clearing caatinga on dry season forage for goats and sheep. In addition, factors affecting litter decomposition on cleared and uncleared caatinga were assessed to evaluate the viability of deferring grazing of forages during the wet season for use later in the dry season.

Removing the trees resulted in a sixfold increase in production of herbaceous vegetation, however, 88 percent of the increased yield on the cleared areas was …


Plant Gas Exchange Of Two Bunchgrasses In Relation To Herbivory Tolerance, Robert S. Nowak May 1984

Plant Gas Exchange Of Two Bunchgrasses In Relation To Herbivory Tolerance, Robert S. Nowak

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The occurrence of compensatory photosynthesis was examined in the field during the spring for all foliage elements on two Agropyron bunchgrass species that differ in their evolutionary history of grazing pressure. Compensatory photosynthesis did occur in many individual foliage elements during at least part of their ontogeny. For both species, compensatory photosynthesis was related primarily to delayed leaf senescence and increased soluble protein concentrations, but not to an improvement in the water status of clipped plants. Photosynthetic water use efficiency and photosynthetic rates per unit soluble protein of foliage on partially defoliated plants were not increased following the clipping treatments. …


Effects Of Folic Acid Or Zinc Malnutrition On Rotaviral Infection In A Murine Model, John Douglas Morrey May 1984

Effects Of Folic Acid Or Zinc Malnutrition On Rotaviral Infection In A Murine Model, John Douglas Morrey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The influences of dietary deficiencies of folic acid or zinc on rotaviral disease infant mice were studied. Preliminary studies indicated that bovine and simian rotaviruses, but not porcine rotavirus, caused diarrhea in infant mice. Bovine and porcine rotaviruses were not, however, sufficiently infectious to replace murine rotavirus in studies utilizing the murine model. It was also determined that murine rotavirus purified by a cesium chloride gradient was highly infectious and useful for subsequent studies on nutritional influences of rotaviral disease. In dietary studies, female Swiss Webster mice were fed diets containing deficient, moderately deficient, or adequate levels of folic acid …


A Lactic Culture Stimulant Blend From Kluyveromyces Fragilis And Whey, Steven L. Wright May 1984

A Lactic Culture Stimulant Blend From Kluyveromyces Fragilis And Whey, Steven L. Wright

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A buffered growth medium was developed that sustained a significantly greater concentration of various strains of Streptococcus lactis and Streptococcus cremoris than did milk. The active buffering ingredients of this medium were magnesium hydroxide, ammonium and sodium salts of phosphate and citrate. This medium was entitled Lactic Culture Buffered Growth medium (LABGRO) and possessed about 8 times the buffering strength between pH 6.6 and 5.1.

Significant differences in growth and acid production rates were noted among Prt+ and Prt- lactic strains evaluated. Also noted were significant differences in cellular acid production rates. The two Prt- strains having the slowest growth …


Protein Recovery And Coagulation Properties Of Commercial And Fractionated Milk Clotting Enzymes, Khalida A. Shaker May 1984

Protein Recovery And Coagulation Properties Of Commercial And Fractionated Milk Clotting Enzymes, Khalida A. Shaker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Protein recovery and coagulation properties of five commercial and fractionated milk clotting enzymes were studied. The fractionated enzymes were Sephadex G-100 fractions of the commercial enzymes. Milk clotting activity of each fraction was tested using Berridge substrate. All fractions from each preparation which had milk clotting activity as measured with the Formagraph were collected and pooled. These samples and the original enzyme preparations were used to coagulate milk. Percent of protein lost in whey was determined by Kjeldahl. Coagulation was followed using a spectrophotometer monitoring changes in apparent absorbance at 600 nm. Curd protein yields using the five original enzyme …


Survival Of Porcine Pepsin During Cheddar Cheese Making And Its Effect On Casein During Cheese Ripening, Gheyath H. Majeed May 1984

Survival Of Porcine Pepsin During Cheddar Cheese Making And Its Effect On Casein During Cheese Ripening, Gheyath H. Majeed

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A modification of a linear diffusion test for measuring milk clotting enzymes at concentrations of 1 x 10-4 to 1 x 10-1 chymosin units/ ml was developed to permit quantitative assay of porcine pepsin in Cheddar cheese with a standard deviation of 6%. The amount of porcine pepsin retained in Cheddar cheese curd was dependent on pH of milk at setting. Milk at pH 6.6, 6.4, 6.2, and 6.0 was set with porcine pepsin, acidified with lactic acid and glucono-~-lactone and made into Cheddar cheese. After pressing the corresponding curd contained 0, 3.64+0 .12 %, 4.79+0.52%, and 5.94+0.30% …