Digital Commons Network^™

Cottage Cheese From Ultrafiltered Skimmilk By Direct Acidification, Jorge Ricardo Ocampo-Garcia

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Pasteurized skimmilk at 4°C was acidified to pH 5.8 with 85.5% phosphoric acid (136g H₃PO₄/100 kg skimmilk), then warmed to 54°C and ultrafiltered to a protein concentration 9.1 ± 0.2%. The retentate was heated to 76.5°C for 16 s then cooled to 2°C. Phosphoric acid (85.5%) was added at a rate of 3.41g per kg retentate. The acidified retentate was slowly warmed to 29.5°C (3°C/5 min) when the pH was checked. The pH at this point was no lower than 5.4. Heating was continued until a temperature of 32.2°C was reached. Glucono delta lactone was added …

The Effect Of Ultrafiltration On Protein Quality Of Skimmilk And Cottage Cheese, Rita Y. Y. Tung

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Protein quality in freeze-dried skimmilk (SM), regular cottage cheese (RCC), retentate (Ret) and cottage cheese made from ultrafiltrated skimmilk (UFCC) were evaluated by chemical (amino acid score) and biological methods. Biological evaluation was at 5, 8 and 11% protein level in growing rats by measuring biological value (BV), net protein utilization (NPU) and nitrogen efficiency for growth (NEG) over a 14-day period. A 28-day protein efficiency ratio (PER) was determined on the same products at 10% protein level. Effects of added lactose on PER of retentate, regular and UFCC were also evaluated. The most limiting amino acids were cystine + …

Factors Affecting Growth Of Proteinase Positive And Proteinase Negative Streptococcus Cremoris Uc310 In Ultrafiltered Milk Retentate, Brent Karl Pope

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Whole milks were adjusted to pH 5.8, 6.2, or 6. 7 with HCl and batch pasteurized at 63°C for 30 min. Each was concentrated 5:1 (40% total solids) through a single tube polysulfone membrane Abcor ultrafiltration unit. Lactose (L), casein hydrolysate (CH), and one of two brands of yeast extract (YE1, YE2) were added into cooled retentates at 0.1, 0.3, 0.5, 0. 7 or 0.9% and equilibrated overnight at 4°C. Five percent proteinase positive (Prt+) Streptococcus cremoris UC 310+ (v/w) milk based culture was added. Unfortified retentate was also inoculated with 0.1, 0.3, 0.5, 0. 7 or 0.9% starter and …

Effect Of Proteolytic Enzymes On Transfection And Transformation Of Streptococcus Lactis Protoplasts And Transformation Of Streptococcus Cremoris, Steven A. Woskow

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effect of proteolytic enzymes on the transformation and transfection of Streptococcus lactis LM2301 protoplasts was examined in an attempt to eliminate the variability observed. By using both chymotrypsin and mutanolysin to form protoplasts followed by spread plating, consistent frequencies of 104 to 105 transformants per μg of pGB301 DNA, and 105 transfectants per μg of c2 bacteriophage DNA where achieved. Optimum transformation and transfection frequencies were obtained when 16 h cultures were treated simultaneously with 25 U/ml mutanolysin and 1.25 U/ml chymotrypsin for 15 min. Trypsin and pronase in conjunction with mutanolysin also increased transformation frequencies higher than when …

The Effectiveness Of Lime-Based Amendments And Bauxite Residues At Removing Phosphorus From Piggery Effluent, D. M. Weaver, G. S. P. Ritchie

Food Science and Nutrition

Piggery effluent may contribute to the eutrophication of waterways, if it is not treated before disposal, because of high levels of phosphorus. Limes and red muds (a residue from bauxite refining) were used to remove phosphorus from piggery effluent (41 mg litre^-1 total P). Lime-based amendments were more effective than the red muds at removing phosphorus when compared at the same liquid: solid ratios. Based on laboratory data, the cost of treating effluent increased rapidly as the final required phosphorus concentration decreased to less than 4 mg litre^-1. Kiln dust was the cheapest amendment tested down to …

Influence Of Delignifying Agents On Tissue Structure In Bermudagrass Stems, D. E. Akin, L. L. Rigsby, F. E. Barton, P. Gelfand, D. S. Himmelsbach, W. R. Windham

Food Structure

Permanganate, dioxane, ozone, and hydrogen peroxide, which delignify plant materials, were evaluated for their disruptive action on plant structure, the ir modification of histological reactions for Iignins, and their change in in vitro digestibility by rumen microorganisms of yollng-Tsecond internode from top) and old (fourth and fifth internodes) bermudagrass stems. Epidermis, sclerenchymaring, and vascular tissue (except phloem) gave positive reactions with acid phloroglucinol (AP) or chlorinesulfite (CS) in all samples , whereas cortex and parenchyma in older stems gave a positive reaction with CS. Treatment with delignifying agents reduced the reactions for lignin, with permanganate- treated tissues having the least …

Fluorescence And Light Microscopic Analysis Of Digested Oat Bran, S. H. Yiu, R. Mongeau

Food Structure

The Structural and chemical compositions of digested oat bran were analyzed by fluorescence and other types of light microscopy. The digestion of oat bran was carried out under two conditions - in vitro, by incubation with human saliva, and in vivo, by feeding rats with an oat-bran supplemented diet. Comparison of the digestive breakdown among different structural components of oat bran was conducted by microscopically examining samples obtained from the tents of the large intestine (LIC) of the rats. Results of the examinations revealed that the (1-3) (1-4) - B - D - glucan - rich cell wall of the …

Effect Of Clotting In Stomachs Of Infants On Protein Digestibility Of Milk, S. Nakai, E. Li-Chan

Food Structure

Differences in clotting between human and cow's milk in the stomachs of infants are discussed. Gastric pH, after ingesting milk, of an infant up to 6 months of age stays at a pH range of 4-5, near the isoelectric point of casein, and never reaches the value of 2, which is found in adults. Pepsin C (or gastricsin) can hydrolyze proteins at this pH range. Gastric emptying time is shorter with human milk than with cow's milk which appears to be correlated to the smaller size of human milk clots. Elimination of a readily coagulable fraction of casein from cow's …

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

Cheese Industry Conference

No abstract provided.

Seed Microstructure And Its Relationship To Water Uptake In Isogenic Lines And A Cultivar Of Dry Beans (Phaseolus Vulgaris L.), George N. Agbo, George L. Hosfield, Mark A. Uebersax, Karen Klomparens

Food Structure

Comparisons using scanning electron microscopy (SEM) were made among seeds of the isogenic bean strains, 'Nep - 2' and 'San Fernando' and 'Sanilac', a navy bean cultivar, to ascertain interrelationships between seed microstructure and water absorption characteristics. During a 90 min soaking period 1:1 (v /v) tap and distilled water, 'San Fernando' hydrated at the s lowest rate and imbibed water at only 60% and 78% of the percentages of water imbibed by 'Sanilac' and 'Nep-2', respec tively. Among the three bean genotypes, 'Sanilac' hydrated the most rapidly and imbibed the most water (5 2.9% ). 'Nep - 2' was …

Textural Properties And Structure Of Starch-Reinforced Surimi Gels As Affected By Heat-Setting, J. M. Kim, C. M. Lee, L. A. Hufnagel

Food Structure

The gel forming behavior of red hake (Urophycis chuss) surimi with and without starch and its relationship to the structure of the gel matrix were studied. For surimi gels without starch, a combination of preheat- setting at 40 C and cooking at 90 C resulted in significantly greater gel strength than cooking alone. However, preheat - setting of gels containing wheat or potato starch had no significant effect on gel strength demonstrating an opposite trend in gel strength due to the differences in swelling power, water holding ability and gelatinization temperature between potato and wheat starches. This difference in gel …

Effects Of Drying Techniques On Milk Powders Quality And Microstructure: A Review, Marijana Caric, Miloslav Kalab

Food Structure

The quality of milk powders is markedly affected by the composition and properties of the milk, the manufacturing procedures, thermal processing during manufacture and, in particular, the drying technique itself. A variety of physico-chemical analytical methods, including scanning electron microscopy, has been used to obtain information on the effects of the various factors on the microstructure of the milk powders. Roller-drying, which has recently lost its commercial importance, produces a sheet of dried milk that is powdered in a hammer mill. The resulting powder consists of compact particles with sharp edges. Powders obtained by spray-drying are in the form of …

Food Quality And Energy Usage In Foodservice Systems: Convective Thermal Processing Of Turkey Rolls, M. E. Matthews, M. E. Zabik, R. B. Maxcy

Department of Food Science and Technology: Faculty Publications

This study evaluated sensory and nutritional qualities, microbioloqical and chemical safety of turkey rolls and enerqy use durinq convective thermal processing. Turkey rolls were heat processed in home or institutional convection ovens to an internal temperature of 77 to 80°C in the geometric center of the roll. Treatment combinations included three heat-processing temperatures (105, 135, and 165°C) and two holding treatments (not chilled and chilled for 24 hr) and three hot-holding times (0, 60 and 120 min). Sensory studies of white turkey meat roasted at 165°C and reheated showed that juiciness decreased significantly (p<0.05), compared to roasting at 105 or 135°C without reheating. Juiciness was also decreased significantly (p<0.05) as hot-holding progressed (0 to 120 min).

Use Of Galactose-Fermenting Streptococcus Thermophilus In The Manufacture Of Swiss, Mozzarella, And Short-Method Cheddar Cheese, Robert W. Hutkins, S.M. Halambeck, H.A. Morris

Department of Food Science and Technology: Faculty Publications

Galactose-fermenting (galactose-posirive) strains of Streptococcus tbermopbilus, alone and combined with galactosepositive and galactose-negative strains of Lactobacillus bulgaricus, were used as starter cultures in the manufacture of Swiss and Mozzarella cheese and were paired with Streptococcus lactis (also galactose-positive) in short-method Cheddar cheese manufacture. Experimental Swiss cheese made with the galactosepositive Streptococcus tbermopbilus starter alone contained a large amount of galactose (ca. 26 to 28 /amol/g of curd) 28 h after hooping compared with control Swiss (< 2/amol/g) made with a nongalactose fermenting strain of Streptococcus tbermopbilus and a galactosepositive strain of Lactobacillus bulgaricus. Mozzarella and short-method Cheddar made with only galactose-positive Streptococcus tbermopbilus also contained …

Effect Of Oxidation-Reduction Potential On Hemochrome Formation And Resultant Pink Color Defect Of Cooked Turkey Rolls, Farzaneh Vahabzadeh

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A pink color defect is commonly observed in freshly cut surfaces of cooked turkey rolls and fades rapidly upon exposure to air. The non uniform pink color makes the product appear undercooked, and the product must be discounted. The oxidation-reduction potential of the meat is important in development of pink defect. A pink color similar to that of commercial product was observed when the cooked meat was treated with either sodium nitrite or sodium dithionite. The pink color in nitrite treated meat was due to nitroso pigment formation, but in samples treated with dithionite the pink color was due to …

Pantothenic Acid Status Of Adolescents, Brenda Ringer Eissenstat

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Information on human needs for pantothenic acid is limited and no recommended daily allowance has been established; although a safe and adequate level of 4-7 mg/day has been suggested for adults and adolescents. The adolescent population is often at risk for nutritional problems because of unusual eating patterns and major physiological changes which occur at this time. Pantothenic acid levels in urine, whole-blood and erythrocytes were determined in a healthy adolescent population using radioimmunoassay techniques. Dietary intakes were calculated from 4 day diet records and evaluated using a computer data base developed at Utah State University in conjunction with USDA. …

Effects Of Micrococci On Improving Sensory Acceptability Of Mutton Summer Sausage, Hoon Jung

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effects of micrococci on sensory characteristics of different batches of summer sausages were determined. Sixty four salt-tolerant indigenous isolates were selected from beef or mutton treated with 1.5 or 3.0% sodium chloride and 120 ppm sodium nitrite, and held at 5 or 10 C for 5 days. These isolates (61/64) were identified as staphylococci and micrococci. Summer sausages were made from several lamb, ewe, and ram carcasses which were hand deboned and blended after grinding to contain 22% fat. Six summer sausage treatments were prepared using two different sources of commercial starter cultures including Micrococcus species or Micrococcus varians …

Natural Cheese From Prefermented Whole Milk Retentate, Charles Gordon Brown

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A new method for manufacture of natural cheese was developed using 5X ultrafiltered whole milk retentate. The retentate was prefermented to pH 5.0-5.2 before curd formation to simplify the cheese making process. It was demonstrated that the process can be made commercially feasible.

Ultrafiltration and diafiltration of whole milk were done so that the desired level of residual lactose was left in the retentate. Retentate was inoculated with lactic starter culture and incubated (prefermented) until all lactose was converted to lactic acid. The final pH stabilized at about 5.0-5.2; the desired pH of the cheese curd. Incubation at 25°C allowed …

Determination Of Internal Color Of Beef Ribeye Steaks Using Digital Image Analysis, K. Unklesbay, N. Unklesbay, J. Keller

Food Structure

Objective measurements of beef ribeye steaks were made to determine the color distribution throughout their interior after heat processing. Steaks from eight animals were grilled to five degrees of doneness according to traditional internal temperature specifications. Images of the interior of these steaks, as seen by a digital image processing system through red, green, and blue filters were analyzed. The mean, standard deviation, skewness, and kurtosis of the histograms of light intensity at all points throughout the surface were determined. The steaks were also analyzed raw and it was determined that little variation in the color of muscle tissue occurred …

Proceedings From The 23rd Annual Marschall Invitational, Various Authors

Cheese Industry Conference

No abstract provided.

Fluorescence Characterization Of The Mature Caryopsis Of Sorghum Bicolor (L.) Moench, C. F. Earp, L. W. Rooney

Food Structure

Fluorescence microscopy was used to characterize the mature car yaps is of Sorghum bicolor (L.) Moench . Acid Fuchsin, a protein specific dye used in bright field microscopy, caused protein bodies and matrix in the sorghum endosperm to fluoresce. ANS (8-ani lino-1- naphthal e ne sulfonic acid) also caused the protein bodi es and matrix in the endosperm to fluoresce. Varietal differences in endosperm protein dist r ibution were evident when viewed after sta · ning with Acid Fuchsin . Nile Blue A caused fl uorescence in neutral lipids such as those in :he lipid bodies in the aleurone and …

Freeze Texturation Of Proteins: Effect Of The Alkali, Acid And Freezing Treatments On Texture Formation, Frisco I. Consolacion, Paul Jelen

Food Structure

The effects of alkali extraction, isoelectric precipitation, and rate of ice crystal formation on protein interaction in the freeze texturization process were studied , The protein isolate was obtained from mechanically deboned poultry meat residues by extraction with NaOH at pH 10.5 and precipitation by HCl at pH 5, 0, The presence of large molecular weight subunits in the protein isolate was revealed by SDS-polyacrylamide gel electrophoresis. Scanning electron microscopy demonstrated the nature of the fiber formation and protein cross-linking as affected by freezing at -25'C or -196'C. The transformation of the level of protein organization from the lumpy or …

Relative Toxicities Of Inorganic Aluminum Complexes To Barley, R. S. Cameron, G. S.P. Ritchie, A. D. Robson

Food Science and Nutrition

The inorganic forms of Al in the soil solution that decrease plant growth in acid soils have not been clearly identified. Therefore, we examined the effects of Al and its complexes with F^- and SO₄^2- on the root elongation of barley (Hordeum vulgare) in nutrient solutions containing 3333 μmol Ca L^-1 and 6 μmol B L^-1 at pH 4.5. The anions were chosen because of their presence in the soil solution at levels sufficient to complex Al. The toxicity of 0 to 100 μmol Al L^-1 was studied in the presence of …

Lupin Processing : A New Development, R S. Coffey

Journal of the Department of Agriculture, Western Australia, Series 4

For a number of years Grain Pool marketing representatives have approachd stockfeed manufacturers around the world in an attempt to broaden the market for Western Australian lupin seed.

Wherever there was enough consumer interest to conduct a nutritional evaluation of the product, lupins were found to be non competitive for inclusion in both pig and poultry rations, while at the same price being acceptable as a cattle feed ingredient. The reason for this disparity proved to be the varying degrees of fibre digestability of lupins for the various livestock tested.

It became apparent that the fibrous lupin seed coat or …

Ultrastructure Of Maize Starch Granules. A Review, Daniel J. Gallant, Brigitte Bouchet

Food Structure

History of starch granule ultrastructure and the principal data obtained on maize starch granules are analyzed. New results are developed: i) growth and development of the maize starch granules during maturation depend on the maize varieties and the tissue site in the kernel, especially the horny and flloury endosperms; ii) cytochemical studies of the starch granules differing from their amylose/amylopectin ratio show important differences in the distribution of their crystalline and amorphous zones that explain their behaviour under some hydrolytic treatments; iii) complexing between colloidal gold labelled concanavalin-A and starch (amylopectin) permits new and greater specificity to ultrastructural study of …

Structural Characteristics Of Eleusine Corocana (Finger Millet) Using Scanning Electron And Fluorescence Microscopy, C. M. Mcdonough, L. W. Rooney, C. F. Earp

Food Structure

The objective of this study was to document the microstructure of finger millet wlth scanning electron and fluorescence microscopies. Finger millet is an utricle which is spheri ca 1 and about 1 . 5 ITlT1 in diameter. The membranous peri carp of finger millet was loosely associated with the seed at maturity. Beneath the loose pericarp wa s a five-layered testa that varied from red to purple in color. The outer layer was the only testa layer that autofl uoresced, suggesting the presence of phenolic acids, i .e., ferulic acid. The aleurone layer was beneath the testa , and was …

Lipolytic Changes In The Milk Fat Of Raw Milk And Their Effects On The Quality Of Milk Products, E. Kirst

Food Structure

Lipolytic changes in milk rat affect sensory attributes and techno logicaI properties of milk and milk products. They are affectcd by physiologal, thermal . and biochemical factors as well as by the mechanics of fluids Lipolytic processes in milk are intensified by modern processing methods.

In this review. special attention has been paid to runinant- related feeding of dairy cows. foaming of milk. mechanical and thermal influences and the growth of psycllrotrophic bacteria.

Feeds deficient in energy affect the chemical composition of the milk fat. Tests have shown that on an average. approximatey 55% of free fatty acids in the …

Microstructure Of Lentil Seeds (Lens Culinaris), Joe S. Hughes, Barry G. Swanson

Food Structure

Scanning electron microscopy (SEM) was used to investigate the microstructure of five cultivars of lentil seeds (Lens culinaris). Lentil cot yledons contain sphericai starch granules surrounded by protein bodies similar to starch granules and protein bodies observed in cotyledons of other food legumes. Examination of the lentil seed coat in cross - section revealed outer palisade and inner parenchyma layers characteris tic of legumes. The subepidermal layer, however, is comprised of hourglass cells and is found primarily in the area surrounding the hilum and the entire lentil seed coat is thinner than the seed coat s of most other food …

Ua35/11 Student Honors Research Bulletin, Wku Honors Program

WKU Administration Documents

The WKU Student Honors Research Bulletin is dedicated to scholarly involvement and student research. These papers are representative of work done by students from throughout the university.

• Padilla, Anne. First and Second Language Acquisition: A Comparison
• Scott, Angela. Salted and Unsalted Snacks: Taste Preferences of Second Grade Students in a Rural Area School
• Fuqua, Nancy. Acceptance by High School Students of Muffins Containing Supplemental Soy Polysaccharides
• Mans, Glee. Preference Levels of High School Freshmen for Four Cheese Food Products
• Denney, Pam. Consumer Acceptance of UHT Choclate Lowfat Milk
• Harris, Carla. Jacques-Louis David: Raphael of the Sansculottes
• Vaughn, James. Corporate Reorganization …

Galactokinase Activity In Streptococcus Thermophilus, Robert W. Hutkins, Howard A. Morris, Larry L. Mckay

Department of Food Science and Technology: Faculty Publications

ATP-dependent phosphorylation of [¹⁴Cigalactose by 11 strains of Streptococcus thermophilus indicated that these organisms possessed the Leloir enzyme, galactokinase (galK). Activities were 10 times higher in fully induced, galactose-fermenting (Gal⁺) strains than in galactose-nonfermenting (Gal-) strains. Lactose-grown, Gal^- cells released free galactose into the medium and were unable to utilize residual galactose or to induce galK above basal levels. Gal⁺ S. thermophilus 19258 also released galactose into the medium, but when lactose was depleted growth on galactose commenced, and galK increased from 0.025 to 0.22 μmol of galactose phosphorylated per min per mg of …