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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 ...


Genomic Characterization Of Dairy Associated Leuconostoc Species And Diversity Of Leuconostocs In Undefined Mixed Mesophilic Starter Cultures, Cyril A. Frantzen, Witold Kot, Thomas B. Pedersen, Ylva M. Ardö, Jeff R. Broadbent, Horst Neve, Lars H. Hansen, Fabio Dal Bello, Hilde M. Østlie, Hans P. Kleppen, Finn K. Vogensen, Helge Holo Feb 2017

Genomic Characterization Of Dairy Associated Leuconostoc Species And Diversity Of Leuconostocs In Undefined Mixed Mesophilic Starter Cultures, Cyril A. Frantzen, Witold Kot, Thomas B. Pedersen, Ylva M. Ardö, Jeff R. Broadbent, Horst Neve, Lars H. Hansen, Fabio Dal Bello, Hilde M. Østlie, Hans P. Kleppen, Finn K. Vogensen, Helge Holo

Nutrition, Dietetics, and Food Sciences Faculty Publications

Undefined mesophilic mixed (DL-type) starter cultures are composed of predominantly Lactococcus lactis subspecies and 1–10% Leuconostoc spp. The composition of the Leuconostoc population in the starter culture ultimately affects the characteristics and the quality of the final product. The scientific basis for the taxonomy of dairy relevant leuconostocs can be traced back 50 years, and no documentation on the genomic diversity of leuconostocs in starter cultures exists. We present data on the Leuconostoc population in five DL-type starter cultures commonly used by the dairy industry. The analyses were performed using traditional cultivation methods, and further augmented by next-generation DNA ...


Growth And Gas Formation By Lactobacillus Wasatchensis, A Novel Obligatory Heterofermentative Nonstarter Lactic Acid Bacterium, In Cheddar-Style Cheese Made Using A Streptococcus Thermophilus Starter, Western Dairy Center, Utah State University, Fatih Ortakci, Jeff R. Broadbent, Craig J. Oberg, Donald J. Mcmahon Nov 2015

Growth And Gas Formation By Lactobacillus Wasatchensis, A Novel Obligatory Heterofermentative Nonstarter Lactic Acid Bacterium, In Cheddar-Style Cheese Made Using A Streptococcus Thermophilus Starter, Western Dairy Center, Utah State University, Fatih Ortakci, Jeff R. Broadbent, Craig J. Oberg, Donald J. Mcmahon

Nutrition, Dietetics, and Food Sciences Faculty Publications

A novel slow-growing, obligatory heterofermentative, nonstarter lactic acid bacterium (NSLAB) Lactobacillus wasatchensis WDC04 was studied for growth and gas production in Cheddar-style cheese made using Streptococcus thermophilus as the starter culture. Cheesemaking trials were conducted using St. thermophilus alone or in combination with Lb. wasatchensis deliberately added to cheese milk at a level of ~104 cfu/ml. Resulting cheeses were ripened at 6 or 12°C. At d 1, starter streptococcal numbers were similar in both cheeses (~109 cfu/g) and fast-growing NSLAB lactobacilli counts were below detectable levels (<102 cfu/g). As expected, Lactobacillus wasatchensis counts were ...


Development Of Methods For Assessing The Effect Of Moisture And Aging On Sliceability Of Cheese, Jess Perrie May 2012

Development Of Methods For Assessing The Effect Of Moisture And Aging On Sliceability Of Cheese, Jess Perrie

All Graduate Plan B and other Reports

Sliceability is a cheese’s ability to cut cleanly into thin slices, resist breakage or fracture at slices edges, and undergo a high level of bending before breaking. Intuitively, sliceability depends on the chemistry, microstructural, and rheological properties of the casein network. Currently there is no reported scientific research investigating evaluation methods of cheese slice quality, as well as properties that influence a cheese’s ability to slice.

In this study, a method for slice quality evaluation was developed on purchased cheese and performed on commercial cheeses and experimental cheeses manufactured at three different moisture contents (40.6%, 37.0 ...


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 ...


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 ...


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 ...


Proceedings From The 34th Marschall Italian And Specialty Cheese Seminar, Various Authors Sep 1997

Proceedings From The 34th Marschall Italian And Specialty Cheese Seminar, Various Authors

Cheese Industry Conference

No abstract provided.


Proceedings From The 33rd Annual Italian And Specialty Cheese Seminar, Various Authors Sep 1996

Proceedings From The 33rd Annual Italian And Specialty Cheese Seminar, Various Authors

Cheese Industry Conference

No abstract provided.


Proceedings From The 32nd Marschall Italian And Specialty Cheese Seminar, Various Authors Sep 1995

Proceedings From The 32nd Marschall Italian And Specialty Cheese Seminar, Various Authors

Cheese Industry Conference

No abstract provided.


Proceedings From The 31st Annual Italian And Specialty Cheese Seminar, Various Authors Sep 1994

Proceedings From The 31st Annual Italian And Specialty Cheese Seminar, Various Authors

Cheese Industry Conference

The impact of mixer temperature and mixer screw speeds on fat recovery, protein recovery, and yield of Mozzarella cheese was determined. In the first trial three different cheese temperatures were achieved: 130·F (54.C); 140•F (60.C); and 150.F (66·q. In the mixer temperature trial, a screw speed of 12 rpm (revolutions per minute) was used at all mixer temperatures. In the second trial, three different mixer screw speeds were used for stretching: 5 rpm, slow; 12 rpm, medium (ca. 50o/o of mixer full speed); 19 rpm, fast. Three vats of cheese were made per ...


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 ...


Proceedings From The 30th Annual Marschall Italian Cheese Seminar, Various Authors Sep 1993

Proceedings From The 30th Annual Marschall Italian Cheese Seminar, Various Authors

Cheese Industry Conference

Our interviews with cheese makers, owners, managers, and top management of mozzarella processing companies across the United States resulted in our quest for accurate data from which an automatic Mozzarella processing systems could be designed.


Practical Aspects Of Electron Microscopy In Dairy Research, Miloslav Kalab Jan 1993

Practical Aspects Of Electron Microscopy In Dairy Research, Miloslav Kalab

Food Structure

Milk products are based mostly on casein micelles, fat globules, and whey proteins. The former two constituents are corpuscular and whey proteins become corpuscular when coagulated. Structural changes in these basic constituents during processing have been studied by electron microscopy. This review discusses the structures of yoghurt, curd, cheeses (hard cheeses, mould-ripened cheeses, cream cheeses, and process cheese), cream, milk powders, and nontraditional dairy products. Defects and deviations from traditional structures of these products are explained where the causes are known. Examples of such causes are foaming of milk, presence of unusual ingredients (bacterial polysaccharides, whey protein concentrates), and alterations ...


High-Resolution Scanning Electron Microscopy Of Milk Products: A New Sample Preparation Procedure, William R. Mcmanus, Donald J. Mcmahon, Craig J. Oberg Jan 1993

High-Resolution Scanning Electron Microscopy Of Milk Products: A New Sample Preparation Procedure, William R. Mcmanus, Donald J. Mcmahon, Craig J. Oberg

Food Structure

A metal-impregnation technique (tannin-ferrocyanide- osmium tetroxide) and thin metal coating imparted excellent preservation , and electric and thermal properties to milk products for scanning electron microscopy, resulting in high- resolution images. Three nanometer resolution was obtained, with minimal edge effects, charging , thermal drift, and decoration. Samples were fixed in 2% gluta raldehyde, cryoprotected in 70% ethanol, and cryofractured, exposing internal structure. Fat was extracted with Freon 113 and the sample were metal -impregnated with 1.0% osmium tetroxide and 1.5% potassium ferrocyanide, reduced with 1% hydroquinone, dried using !he critical-point drying melhod , and ion beam sputter-coated with 2-5 nm of ...


Age Related Changes In The Microstructure Of Mozzarella Cheese, L. J. Kiely, P. S. Kindstedt, G. M. Hendricks, J. E. Levis, J. J. Yun, D. M. Barbano Jan 1993

Age Related Changes In The Microstructure Of Mozzarella Cheese, L. J. Kiely, P. S. Kindstedt, G. M. Hendricks, J. E. Levis, J. J. Yun, D. M. Barbano

Food Structure

Changes that occurred in the microstructure of low-moisture, part skim Mozzarella made with a mixed starter consisting of Streptococcus salivarius ssp. thermophilus and Lacwbacillus delbrueckii ssp. bulgaricus and coagulated with fermentation -produced chymosin , were examined during 50 days of ripening at 4 °C. Im mediately after manufacture (day 3), a homogeneous and continuous phase of amorphous paracasein represented a three-dimensional protein network in the cheese. A large number of irregularly shaped and sized microcavi ties were present. During 50 days of aging , an increase in the porosity of the defatted paracasein matrix was apparent. These changes were coincidental with a ...


Proceedings From The 29th Annual Marschall Italian Cheese Seminar, Various Authors Sep 1992

Proceedings From The 29th Annual Marschall Italian Cheese Seminar, Various Authors

Cheese Industry Conference

Three 375 lb vats of cultured low moisture pan skim Mozzarella cheese were produced from the same batch of standardized milk and rennet, but using three different rod (Lactobacillus bulgaricus - Marschall ProduciS - Thennorod) and coccus (Streptococcus thermophilus - Mar chall Product - Thennococcus) ratios (9R:IC, 5R:5C, and !R:9C). The total volume and total colony fonning units of culture added was kept constant for all ratios (i.e., I 02 ml/375 I b). Cheese was made with the ·'no-brine·· chee e making method using a I06°F (41° ) cook temperature, 6.4 draw pH *whey), 5.25 milling pH ...


Effect Of Draw Ph On The Development Of Curd Structure During The Manufacture Of Mozzarella Cheese, L. J. Kiely, P. S. Kindstedt, G. M. Hendricks, J. E. Levis, J. J. Yun, D. M. Barbano Jan 1992

Effect Of Draw Ph On The Development Of Curd Structure During The Manufacture Of Mozzarella Cheese, L. J. Kiely, P. S. Kindstedt, G. M. Hendricks, J. E. Levis, J. J. Yun, D. M. Barbano

Food Structure

The impact of varying the pH of whey at whey drainage (5.9, 6.15 or 6.4) on the development of curd structure during the manufacture of Mozzarella cheese was investigated using scanning electron microscopy. Dramatic changes in curd structure were apparent with stage of manufacture , in particular the stretching step which aligned the protein fibers.

Of additional interest is the effect of draw pH on the structure of curd at whey drainage. When whey was drained at pH 6.4, an open poorly fused network of paracasein particles was observed in the cheese curd. Jn contrast, lowering the ...


Proceedings From The 28th Annual Marschall Italian Seminar, Various Authors Sep 1991

Proceedings From The 28th Annual Marschall Italian Seminar, Various Authors

Cheese Industry Conference

Since 1983, the Wisconsin Milk Marketing Board, funded by the 33,000 dairy farmers, has formed a unique partnership with the Wisconsin cheese manufacturers in their efforts to market the products they make with advertising, promotion, education and research programs.

These marketing programs have focused on Wisconsin's cheese quality and cheese making expertise as the foundation for the strategic direction that WMMB has set for our programs and services. Communications strategy was developed to capitalize on the equity in the name "Wisconsin" which has been confirmed through consumer and foodservice market research.

This presentation will give an overview of ...


Structure And Rheology Of Dairy Products: A Compilation Of References With Subject And Author Indexes, David N. Holcomb Jan 1991

Structure And Rheology Of Dairy Products: A Compilation Of References With Subject And Author Indexes, David N. Holcomb

Food Structure

No abstract provided.


Proceedings From The 27th Annual Marschall Italian Cheese Seminar, Various Authors Sep 1990

Proceedings From The 27th Annual Marschall Italian Cheese Seminar, Various Authors

Cheese Industry Conference

No abstract provided.


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 ...


Proceedings From The 26th Annual Marschall Italian Cheese Seminar, Various Authors Jan 1989

Proceedings From The 26th Annual Marschall Italian Cheese Seminar, Various Authors

Cheese Industry Conference

No abstract provided.


Amino Acid Composition And Structure Of Cheese Baked As A Pizza Ingredient In Conventional And Microwave Ovens, Alenka Paquet, Miloslav Kalab Jan 1988

Amino Acid Composition And Structure Of Cheese Baked As A Pizza Ingredient In Conventional And Microwave Ovens, Alenka Paquet, Miloslav Kalab

Food Structure

Amino acid compositions of stirred-curd Mozzarella, stretched Mozzarella, and process Cheddar cheeses were similar and did not change as the result of baking in a conventional oven. D-glutamic acid (D0Glue) and D-phenyl-alanine (D-Phe) were present at low concentrations in all cheese samples, the lowest concentrations having been found in unbaked stirred-curd Mozzarella cheese (2.7% D-Glu of total Glu present and <1.0% D-Phe of total Phe present). The highest concentrations were detected in unbaked stretched Mozzarella cheese (5.6% and 1.2%, respectively). Thechanges were not significant and were not the result of aking, indicating that the heat treatment during baking did n ot cause racemization of the amino acids.

Each cheese had a characteristic structure before baking. The structures of the Mozzarella cheeses were altered by baking in the conventional oven and also in a microwave oven and their original features such as curd granule junction and fat ...


Proceedings From The 25th Annual Italian Cheese Seminar, Various Authors Jan 1988

Proceedings From The 25th Annual Italian Cheese Seminar, Various Authors

Cheese Industry Conference

No abstract provided.


Proceedings From The 24th Annual Marschall Italian Cheese Seminar, Various Authors Jan 1987

Proceedings From The 24th Annual Marschall Italian Cheese Seminar, Various Authors

Cheese Industry Conference

No abstract provided.


The Size Distribution And Shape Of Curd Granules In Traditional Swiss Hard And Semi-Hard Cheeses, M. Ruegg, U. Moor Jan 1987

The Size Distribution And Shape Of Curd Granules In Traditional Swiss Hard And Semi-Hard Cheeses, M. Ruegg, U. Moor

Food Structure

Curd granule junction patterns in hard (Emmentaler, Gruyere, Sbrinz) and semi-hard cheeses (Appenzeller , Tilsiter, Raclette) were visualized on slices and examined using light microscopy and digital image analysis. Horizontal and vertical sections were cut in different zones of the loaves, in order to obtain information on the orientation of the flattened curd granules.

The frequency histograms of the cross section areas could in most cases adequately be described as a log-normal distribution. The median values ranged from 0.97 to 1.15 mm2 and, from 1.31 to 1.68 mm2 for hard and semi-hard cheeses, respectively.

An elliptical form ...