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The Influence Of Protein Concentration And Homogenization On Moisture Content, Curd Yield, And Fat Retention Of Model Cheese Made From Microfiltered Skim Milk Recombined With Cream, Richard Byron Geslison May 2020

The Influence Of Protein Concentration And Homogenization On Moisture Content, Curd Yield, And Fat Retention Of Model Cheese Made From Microfiltered Skim Milk Recombined With Cream, Richard Byron Geslison

All Graduate Theses and Dissertations

This project was funded by the Western Dairy Center at Utah State University as part of a multi-pronged approach to improve the current understanding of using concentrated milks in cheese making. Concentrated milk for this study was provided by South Dakota State University.

This study compared the effect of different concentration factors of milk on curd moisture levels, fat content, and cheese curd yields. To see if these results could be improved (i.e. remove more moisture and retain more fat) milk samples were also subjected to limited pressure homogenization (microfluidization) treatments.

It was found in the course of this ...


Comparison Of Methods For Extracting Lactobacillus Wasatchensis Dna From Broth Media, Milk, And Cheese For Subsequent Pcr-Based Analyses, Tyler Allen Dec 2018

Comparison Of Methods For Extracting Lactobacillus Wasatchensis Dna From Broth Media, Milk, And Cheese For Subsequent Pcr-Based Analyses, Tyler Allen

All Graduate Theses and Dissertations

The Western Dairy Center at Utah State University funded this project as part of its BUILD Dairy program with support from the dairy farmers of Idaho, to investigate the problem of splits that form in cheese during storage. The bacteria, Lactobacillus wasatchensis had previously been identified as a cause of unwanted gas production in cheese and the defects then make the cheese unsuitable for cutting into slices.

The project team proposed a two-year, $150,912 project to investigate methods for determining the presence of this bacterium in cheese by extracting DNA from the cheese and looking for DNA that was ...


Growth Characteristics Of Lactobacillus Wasatchensis And Its Detection And Enumeration Using Quantitative Polymerase Chain Reaction, Isaac Brockbank Bowen Aug 2018

Growth Characteristics Of Lactobacillus Wasatchensis And Its Detection And Enumeration Using Quantitative Polymerase Chain Reaction, Isaac Brockbank Bowen

All Graduate Theses and Dissertations

There are numerous challenges encountered during the manufacturing and storage of cheese by both the large-scale and artesian producers. One such challenge has been the formation of late gassy defect, which occurs when gas is produced by certain lactic acid bacteria found in the cheese block during storage and aging over a three month time period. Negative consequences of late gas production are slits and cracks in the cheese block and puffy cheese packaging, which cause significant financial losses for manufacturers along with poor consumer acceptance.

Lactobacillus wasatchensis is one such lactic acid bacterium shown to produce gas during cheese ...


Contribution Of A Novel Obligatory Heterofermentative Nonstarter Lactobacillus Species To Late Gassy Defect In Cheddar Cheese, Fatih Ortakci May 2015

Contribution Of A Novel Obligatory Heterofermentative Nonstarter Lactobacillus Species To Late Gassy Defect In Cheddar Cheese, Fatih Ortakci

All Graduate Theses and Dissertations

This study sought to determine whether a recently isolated slow-growing nonstarter lactic acid bacterium, Lactobacillus wasatchii sp. nov., could be implicated in late gassy defect in Cheddar cheese. I demonstrated that Lb. wasatchii grows readily in the laboratory under cheese-like stress conditions of 5% salt and pH 5.2, and has the potential to survive pasteurization. Lactobacillus wasatchii can co-utilize ribose and galactose to maximize its growth. Due to being an obligatory heterofermentative, Lb. wasatchii produces CO2 whenever it ferments a hexose such as galactose.

A second investigation extended these findings by examining the growth and gas forming characteristics ...


Characterization Of Volatile And Metabolite Compounds Produced By Lactococcus Lactis In Low-Fat And Full-Fat Cheddar Cheese Extract, Michael J. Young Aug 2011

Characterization Of Volatile And Metabolite Compounds Produced By Lactococcus Lactis In Low-Fat And Full-Fat Cheddar Cheese Extract, Michael J. Young

All Graduate Theses and Dissertations

This study was conducted to compare and contrast potential aroma compounds in the headspace and small molecule metabolites produced as a result of starter culture metabolism in a full-fat and low-fat cheddar cheese model system. Past studies have indicated differences in the headspace flavor compound profiles between full-fat and low-fat Cheddar cheeses with no indication as to what compounds were produced as a result of starter culture metabolism.

Starter cultures were incubated in a Cheddar cheese extract environment that was made up of the water-soluble portion of Cheddar cheese with environmental conditions mimicking full-fat and low-fat Cheddar cheese by altering ...


Investigating The Strategies To Improve The Quality Of Low-Fat Mozzarella And Cheddar Cheeses, Ranjeeta Wadhwani May 2011

Investigating The Strategies To Improve The Quality Of Low-Fat Mozzarella And Cheddar Cheeses, Ranjeeta Wadhwani

All Graduate Theses and Dissertations

Low-fat cheese faces great challenges associated with its texture being hard and rubbery, desirable flavors being missing, color being undesirably intense and translucent appearing, and melting being improper. In an effort of improving the quality of low-fat cheeses, several strategies have been tried to accomplish three major objectives, 1) improving the melting and baking properties of low-fat Mozzarella cheese, 2) improving the color of low-fat Cheddar cheese, and 3) investigating the feasibilities of enriching low-fat Cheddar cheese with dietary fibers.

For objective 1, 4 batches of low-fat Mozzarella cheese with target fat of 6.0%, 4.5%, 3.0%, and ...


Comparative Performance Of Fluorometry And High Performance Liquid Chromatography In The Detection Of Alfatoxin M1 In Two Commercial Cheeses, Gustavo Pena May 2010

Comparative Performance Of Fluorometry And High Performance Liquid Chromatography In The Detection Of Alfatoxin M1 In Two Commercial Cheeses, Gustavo Pena

All Graduate Theses and Dissertations

Aflatoxin M1 (AFM1) is frequently found in milk and dairy products. It is a metabolite formed in cows from aflatoxin B1 (AFB1), contained in animal feeds. In cheese production AFM1 distributes between curds and whey. In this study, cows were fed 64 µg/AFB1/d for the high treatment, and 5 µg/AFB1/d for the low treatment, to obtain milk contaminated with AFM1 over the 0.5 µg/L and under 0.05 µg/L restrictions, respectively. Cheese was manufactured with milk contaminated with AFM1 at 0.8 and 0.03 ìg/kg by the higher and lower treatment ...


The Effect Of Exopolysaccharide-Producing Streptococcus Thermophilus Mr1c On Functionality In High Moisture Cheddar-Type Cheese, Tyler J. Singleton May 2007

The Effect Of Exopolysaccharide-Producing Streptococcus Thermophilus Mr1c On Functionality In High Moisture Cheddar-Type Cheese, Tyler J. Singleton

All Graduate Theses and Dissertations

Differences in texture at any particular stage of ripening depend upon differences in the basic structure and the extent to which the basic structure is modified by physical parameters. Thus, very young cheeses of the same variety differ in texture because of variations in pH and in salt, moisture, and fat content. How well a cheese melts and shreds depend on its texture and physical parameters. Streptococcus thermophilus MR1C produces an exopolysaccharide (EPS) that is tightly associated with the bacterial cell wall. Addition of S. thermophilus MR1C to the cheese make will increase the moisture of the cheese 2-3% and ...


Effect Of Chemical Parameters On Structure-Function Relationships Of Cheese, Andres J. Pastorino May 2002

Effect Of Chemical Parameters On Structure-Function Relationships Of Cheese, Andres J. Pastorino

All Graduate Theses and Dissertations

The effect of chemical parameters on cheese structure and functionality was studied by modifying the calcium, salt content, and pH of cheese. Cheese blocks were high-pressure injected from zero to five times with water, solutions of different salts, or an acid solution 14 d after manufacture. Successive injections were performed 24 h apart. After 40-42 d of refrigerated storage, cheese structure was studied by using scanning electron microscopy and digital image analysis, and cheese functionality was characterized by texture profile analysis and melting test.

Increased salt content of cheese (2.7 versus 0.1%) caused the protein matrix to become ...


The Effect Of Exopolysaccharide-Producing Cultures On The Moisture Retention And Functional Properties Of Low Fat Mozzarella Cheese, David B. Perry May 2000

The Effect Of Exopolysaccharide-Producing Cultures On The Moisture Retention And Functional Properties Of Low Fat Mozzarella Cheese, David B. Perry

All Graduate Theses and Dissertations

Low fat Mozzarella cheese was made using exopolysaccharide-producing starter cultures consisting of single strains of Streptococcus thermophilus MR-1C and Lactobacillus delbrueckii ssp. bulgaricus MR-1R with or without the addition of mesophilic exopolysaccharide-producing adjunct mixed culture consisting of Lactococcus lactis ssp. lactis and Lactococcus lactis ssp. cremoris. A control cheese was made using a non-exopolysaccharide-producing starter culture consisting of S. thermophilus TA061 and Lactobacillus helveticusLH100. Cheeses were analyzed for moisture, melt, fat, and protein. Cheeses made with the addition of the mesophilic exopolysaccharide-producing adjunct culture showed significant differences in moisture, but not in melting properties when compared to cheeses made ...


Influence Of Carbohydrate Starvation On The Culturability And Amino Acid Utilization Of Lactococcus Lactis, Mark R. Stuart May 1999

Influence Of Carbohydrate Starvation On The Culturability And Amino Acid Utilization Of Lactococcus Lactis, Mark R. Stuart

All Graduate Theses and Dissertations

Lactococci are widely used in the cheese industry as a starter culture. Starter cultures face carbohydrate starvation due to the absence of a fermentable carbohydrate in the cheese curd after pressing. Starvation leads to a decreased ability to synthesize ATP, generate a proton motive force, and accumulate nutrients necessary to maintain viability. The aim of this work was to investigate the culturability of lactococci grown with and without lactose in a chemically defined medium, and to define the metabolic changes that occur during carbohydrate starvation.

Lactose metabolism provided energy for logarithmic phase growth and greater cell density in L. lactis ...


Improving Fat Retention And Texture In Low-Moisture Cheese Manufactured From Ultrafiltered Milk, Brian J. Orme May 1998

Improving Fat Retention And Texture In Low-Moisture Cheese Manufactured From Ultrafiltered Milk, Brian J. Orme

All Graduate Theses and Dissertations

Three serious problems have been experienced in the manufacture of low moisture cheese using ultrafiltration (UF)- high fat-loss, excessive moisture retention, and poor cheese texture. In this work the causes of these problems were identified, and means of overcoming them were developed.

Coagulation and cheese-making experiments indicated that UF concentration of milk shifts the control of rennet coagulation toward the casein micelle collision rate and away from rennet activity, resulting in formation of a rough-textured curd structure that resists syneresis. Use of 4x whole milk retentate, instead of 5x, improved rennet curd structure, syneresis, and UF cheese texture without reducing ...


Tryptophan Catabolism By Lactobacillus Spp. : Biochemistry And Implications On Flavor Development In Reduced-Fat Cheddar Cheese, Sanjay Gummalla May 1998

Tryptophan Catabolism By Lactobacillus Spp. : Biochemistry And Implications On Flavor Development In Reduced-Fat Cheddar Cheese, Sanjay Gummalla

All Graduate Theses and Dissertations

Amino acids derived from the degradation of casein in cheese serve as precursors for the generation of key flavor compounds. Microbial degradation of tryptophan (Trp) is thought to promote formation of aromatic compounds that impart putrid fecal or unclean flavors in cheese, but pathways for their production have not been established. This study investigated tryptophan catabolism by Lactobacillus casei LC301 and LC202 and Lactobacillus helveticus CNRZ32 and LH212 cheese flavor adjuncts in carbohydrate starvation (pH 6.5, 30 or 37°C, no sugar) and cheese-like conditions (pH 5.2, 4% NaCl, 15°C, no sugar). Enzyme assays of cell-free extracts ...


Consumption Of Iron-Fortified Cheese And Lipid Peroxidation In Females, Gene J. Giunti May 1994

Consumption Of Iron-Fortified Cheese And Lipid Peroxidation In Females, Gene J. Giunti

All Graduate Theses and Dissertations

Dairy products are important sources of calcium and other nutrients but are a poor source of dietary iron. Cheese comprises a substantial portion of dairy food consumption and has been determined an appropriate medium for iron-fortification. However, iron may promote the potentially harmful process in food and biological systems known as lipid peroxidation. Therefore, the safety of consuming iron-fortified cheese was examined.

Commercial-scale batches of Cheddar cheese were iron-fortified to a level of two milligrams of iron per ounce with either ferric chloride, ferric-casein complex, or ferric-whey protein complex. Fifty-four premenopausal females were divided into three treatment groups and supplemented ...


Effect Of Proteolytic Activity Of The Lactic Cultures On Mozzarella Cheese Quality, Wen-Hsu Amos Wang May 1989

Effect Of Proteolytic Activity Of The Lactic Cultures On Mozzarella Cheese Quality, Wen-Hsu Amos Wang

All Graduate Theses and Dissertations

The Mozzarella cheese market is growing rapidly. Major concerns with cheese meltability and color have arisen in the fast food industry. Pre starter culture was used in this study to improve the physical properties of Mozzarella cheese. Three tests (stretch test, melt test, and browning test) were modified to evaluate the quality of cheese.

A stretch test using the Brookfield helipath viscometer to stretch the cheese sample at 60°C was successful in distinguishing cheeses from different make procedures and from different proteolytic strains. A melt test using a glass tube to hold the cheese flow at 110°C for ...


Effects Of Exercise And Cheese Supplemented Diet On Cholesterol And Lipoprotein Fractions In Free-Living Young Human Subjects, Kathleen A. Gabel May 1987

Effects Of Exercise And Cheese Supplemented Diet On Cholesterol And Lipoprotein Fractions In Free-Living Young Human Subjects, Kathleen A. Gabel

All Graduate Theses and Dissertations

Ten young adults were divided into an exercising group (n = 6) and sedentary group (n = 4). Smoking, ingestion of alcohol, drugs and oral contraceptives were prohibited during 9 weeks of study. Diets were prepared by university food service. Food consumed was recorded and nutrient intakes were assessed. Cheese was consumed in 84 to 112 gram portions every day for two separate 14 day periods. All other dairy products were prohibited in the diet except 240 ml of two percent milk per day. When cheese was consumed, daily diets contained ca 400 kcal, 100 mg cholesterol, and 700 mg calcium more ...


A Process Incorporating Ultrafiltration Concentrated Whey Solids Into Cheese For Increased Cheese Yield, Rodney Jay Brown May 1977

A Process Incorporating Ultrafiltration Concentrated Whey Solids Into Cheese For Increased Cheese Yield, Rodney Jay Brown

All Graduate Theses and Dissertations

A process which incorporates whey sol ids, primarily protein, into cheese to increase cheese yield and eliminate whey handling problems was evaluated. Whey was concentrated by ultrafiltration to levels of 9.8 to 20.3 percent total solids (4.3 to 7.1 percent protein), heated at 70 C for 30 minutes and added to cheese milk with the coagulating enzyme.

Increase in cheese yield, on the basis of 39 percent moisture, for 10 pairs of samples was 4.0 ± 2.8 (S.D.) percent. This increase was significant at alpha less than 0.001. Moisture and protein content increased ...


Persistence Of Mucor Miehei Protease In Cheddar Cheese And Pasteurized Whey And It's Effect Of Sterile Milk Products, Randall Kirk Thunell May 1977

Persistence Of Mucor Miehei Protease In Cheddar Cheese And Pasteurized Whey And It's Effect Of Sterile Milk Products, Randall Kirk Thunell

All Graduate Theses and Dissertations

Whey from a commercial cheese plant, taken at draining on five separate days, from cheese made with a Mucor miehei coagulant was cooled within 1 h to 4 C. Portions were adjusted from pH 4.2 to 6.4 at .2 pH intervals and subjected to HTST pasteurization at 73.9, 76.6, and 79.5 C for 25 sec. Milk clotting activity in whey was determined before and after pasteurization. Resistance to heat in-activation increased with decreasing pH. All measurable activity was destroyed above pH 5.4 by pasteurization at 79.5 C, above pH 5.8 at 76 ...


Manufacture Of Monterey Cheese From Preacidified Milk, Faisal O. Mohamed May 1974

Manufacture Of Monterey Cheese From Preacidified Milk, Faisal O. Mohamed

All Graduate Theses and Dissertations

Whole milk acidified to pH 5.3 with hydrochloric acid was used for the manufacture of Monterey cheese. The milk was inoculated with one and one-half percent lactic starter and set with 12.5 ml rennet per 1000 pounds of milk. Normal washing treatments resulted in cheese with moisture in excess of 44 percent. Moisture content was brought below 44 percent by using wash water at a temperature such that the water-curd whey mixture was 35 C. The pH of cheese made by preacidification was all between 5.21 and 5.09. No acid defects were encountered. Preacidification eliminated chance ...


Detection And Quantitation Of Staphylococcus Aureus Deoxyribonuclease In Cheese, Cyril Newell Maughan May 1972

Detection And Quantitation Of Staphylococcus Aureus Deoxyribonuclease In Cheese, Cyril Newell Maughan

All Graduate Theses and Dissertations

A specific method has been developed for the extraction and measurement of staphylococcal nuclease in cheese in which Staphylococcus aureus has grown. Ten grams of cheese sample were homogenized with ninety milliliters of pH ten buffer for three minutes. Ammonium sulfate fractionation was used and a forty to eighty percent fraction was collected and concentrated using ultrafilters. The nuclease activity was determined using a toluidine blue deoxyribonucleic acid agar slide method and a spectophotometric method. The DNA agar slide method was used to compare staphylococcal growth with nuclease production in cheese under varying conditions. When Staphylococcus aureus plate counts indicated ...


Pasteurized Versus Raw Milk In Brick Cheese-Making, Z. Doyle Roundy May 1933

Pasteurized Versus Raw Milk In Brick Cheese-Making, Z. Doyle Roundy

All Graduate Theses and Dissertations

The prime object of the work undertaken in the present study has been done with the view of determining whether or not the quality and yield of brick cheese may be improved by pasteurizing the milk from which the cheese is made. An effort should be made to put brick cheese-making on a more scientific basis and at the same time produce cheese of better and more uniform quality. Since milk, containing large numbers of undesirable microorganisms thus causing objectionable flavors and odors in dairy products, is frequently delivered to cheese factories to be processed, pasteurization seems to be one ...