Food Science Commons^™

The Use Of Modified Atmoshere Packaging And Phosphate-Citric Acid Dip To Extend The Shelf Life Of Fresh Catfish, Ictalurus Punctatus, Brian Preston Moore

Masters Theses

Ninety market size catfish (Ictalurus punctatus) 1 - 2 pounds live weight were slaughtered, dipped in one of three solutions (phosphate, phosphate + citric acid, no dip) then packaged in one of three atmospheres (100% CO₂, 70% CO₂ + 5% O₂ + 25% N, Air) and were stored at 1^oC or 5^oC. The catfish were evaluated for aerobic plate count, anaerobic plate count, lactic acid count, coliform count, pH, oxidation, drip loss, color and odor at 0, 4, 8, 12 and 16 days. The 100% CO₂ and 70% CO₂ atmospheres …

The Effect Of Heat Treatments On Dietary Fiber As Assessed By Chemical Analysis And Scanning Electron Microscopy, Ming-Cheng Chang

Masters Theses

Today it is generally accepted by many nutritionists that dietary fiber plays an important role in human health. Increased consumption of dietary fiber is advocated for beneficial effects on human health; thus food technologists and the food industry are interested in the use of fiber as an ingredient in food products and in the manufacture of high fiber foods. Numerous researchers have concentrated on the physiological effects of dietary fiber, while few have investigated the effect different processing parameters have on dietary fiber.

Apple fiber, corn fiber, oat bran and soy fiber were prepared and analyzed after further processing (autoclaving …

Chemical Evaluation And Biological Vitamin A Activity Of The Major Carotenoids In The Hybrid Carrot Beta Iii, Cynthia M. Schweitzer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Genetically enhanced high-carotene Beta III hybrid carrot was compared to a commercial carrot cultivar, Nantes Coreless, for carotene content and macronutrient composition. Beta III contained more than twice the total carotene content of Nantes Coreless, with α-carotene/β-carotene ratios higher in Beta III. Total solids from protein, lipids, and carbohydrate were greater in Beta III than in Nantes Coreless. Beta III contained about five times the amount of sucrose and one-fifth the amount of glucose and fructose than Nantes Coreless or reported literature values.

Comparison of the bioavailability of carotenes in Beta III and Nantes Coreless to purified β-carotene and retinyl …

Plasmin In Milk: Activity Measurement, Effect Of Environmental Factors, And Correlation With Milk Coagulation, Eric D. Bastian

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Bovine plasmin activity was measured on H-D-valyl-L-leucyl-L-lysyl-4-nitroanilide by following absorbance changes at 405 nm. Steady-state kinetic parameters V_max, K_m, K_I, and K_I' were estimated. Bovine plasmin is competitively inhibited by casein and has a K_cat of .0158 ΔA₄₀₅/min/nM, K_m of .107 mM substrate, and K_I of .86 mg/ml casein. Bovine plasmin can be measured directly in bovine milk without interference from casein.

A total of 380 milk samples from nineteen Holstein (one herd) and nineteen Jersey (one herd) cows was collected monthly during one lactation period. Samples …

Influence Of Processing Parameters On Nutrient Recovery During Ultrafiltration Of Milk And Meltability Of Pasteurized Process Cheese Food Made From The Retentate, Susan Kay Fortier Collinge

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Three batches of milk were ultrafiltered to 60, 65, or 70% volume reduction before diafiltration. Starting diafiltration at 70% volume reduction took less time and water without affecting nutrient recovery.

Whole milk was heated to 60, 72, and 82°C for 16 s. Milk representing each heat treatment was divided into three batches, one unacidified (pH 6.6), the others acidified to pH 6.2 and 5.8. The milk was ultrafiltered, diafiltered, and concentrated to 5x (80% volume reduction). Retentate was inoculated with .5% lactic culture and incubated at 28°C to pH 5.1. Each lot of fermented retentate was evaporated under 76 kPa …

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

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

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 60 min …

A Quantitative Assessment Of Minerals Of Toxicological Importance In Utah Fast Foods, Lisa R. Williams

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

X-ray flourescence (XRF) and atomic absorption spectrophotometry (AAS) measurements for manganese, iron, copper, and zinc were compared for 96 samples of 21 foods from different sources. Correlation coefficients were 0.94 for manganese, 0.99 for iron, 0.93 for copper, and 0.91 for zinc for XRF vs. AAS determinations.

Similiar comparisons were performed on 228 samples of fast foods purchased in Utah retail outlets. Correlation coefficients ranged from 0.91 for copper to 0.97 for iron and zinc. Comparisons of values generated by XRF for manganese, iron, copper, zinc, selenium, arsenic, and aluminum to values certified by the National Bureau of Standards indicated …

Proteolytic Activity Of Some Milk-Clotting Enzymes On K-Casein And K-Casein Macropeptide, Khalid M. Shammet

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This work reviews studies of bovine K-casein and specifically K-casein macropeptide. Properties of K-casein, its structure and heterogeneity, proteolytic activity of some milk clotting enzymes on K-casein, and K-casein sensitive bonds are discussed. Macropeptides of other species are also presented. The carbohydrate moieties of bovine macropeptide together with their biological and physiological functions are reviewed.

Macropeptides were produced by enzymic hydrolysis from whole casein solution using crystalline chymosin (EC 3.4.23.4). Trichloroacetic acid (final concentrations 2, 8 and 12%) was added after 5, 30 and 60 min of incubation to precipitate protein and inactivate the enzyme. The filtrate was then exhaustively …

Physical And Sensory Properties Of High-Fiber, Reduced-Fat Biscuits, Pamela J. Stanyon

Masters Theses

Rolled biscuits were prepared with 0, 14, 28, and 42% wheat bran substituted for flour and 0, 20, 40, and 60% polydextrose substituted for hydrogenated shortening. Effects on physical and sensory characteristics of biscuits containing 16 combinations were determined with response surface methodology. Wheat bran decreased volume and produced harder, gummier, and chewier biscuits. Panelists indicated crumblier, drier, and chewier biscuits as bran level increased. Unlike wheat bran, polydextrose increased volume and decreased hardness. Panelists scored biscuits made with polydextrose as more moist, but no more chewy than biscuits made without polydextrose. Polydextrose appeared to impede some of the negative …

Attachment And Proliferation Of Bacteria On Meat, James S. Dickson, King-Thom Chung, John D. Crouse

James S. Dickson

The attachment of bacteria (Serratia marcescens, Staphylococcus aureus, Streptococcus faecalis, Salmonella arizonae, Pseudomonas aeruginosa, and Listeria monocytogenes), to lean muscle tissue and fat tissue was investigated. The number of cells attached to the meat was directly proportional to the initial cell concentrations present. There was no significant difference in the number of cells attached between the lean muscle tissue and fat tissues among the organisms tested. All bacteria tested except P. aeruginosa proliferated better on the lean muscle tissues than on the fat tissue at ambient temperature for 72 h. No significant attachment competition to tissue samples was seen between …

Function Of Preliminary Incubation Of Raw Milk Samples For Quality Control, R. Burt Maxcy, Michael Liewen

Department of Food Science and Technology: Faculty Publications

Preliminary incubation of raw milk samples to evaluate bacterial quality has been a commonly recommended practice. The presumption has been that selective growth of a segment of the microflora associated with unsanitary methods and conditions would be enhanced. The present work involved a theoretical approach to evaluate this presumption. Pure cultures of Pseudomonas aeruginosa, P. fluorescens, and Escherichia coli as well as enriched mixed cultures of psychrotrophs and mesophiles were used. The generation time of each culture was determined at various temperatures. An analysis of covariance showed the coefficients of generation time related to temperature were not significantly different. …

Changes With Time In The Availability Of Soil Applied Zinc To Navy Beans And In The Chemical Extraction Of Zinc From Soils, J. D. Armour, G. S.P. Ritchie, A. D. Robson

Food Science and Nutrition

The effect of the incubation of zinc (Zn) applied to the soil on Zn uptake and the Zn concentrations in chemical extractants was studied. In a glasshouse experiment using a Zn-deficient gravelly sandy loam, the effect of recently applied Zn was compared with that of Zn incubated with the soil for 15 days at 40°C on growth and Zn uptake by navy beans (Phaseolus vulgaris cv. Gallaroy). At the second harvest (33 days after sowing), the dry weight of shoots of recently applied Zn was consistently higher than that of incubated Zn, except at the highest rate of 1 …

Soluble And Insoluble Dietary Fiber In Cooked Common Bean (Phaseolus Vulgaris) Seeds, Joe S. Hughes, Barry G. Swanson

Food Structure

The common bean (Phaseolus vulgaris) requires cooking for extended periods of time prior to consumption. In this investigation both quantitative and microstructural changes in common bean dietary fiber as a result of cooking were examined. Cooking resulted in a slight decrease in soluble dietary fiber and a marked increase in insoluble dietary fiber. The increase in insoluble dietary fiber was responsible for a 15 -30 percent increase in total dietary fiber.

Scanning electron microscopy was used to examine the microstructure of uncooked and cooked bean flours and the insoluble and soluble dietary fiber fractions of these two fl ours. In …

Heat-Set Gels Based On Oil/Water Emulsions: An Application Of Whey Protein Functionality, R. Jost, F. Dannenberg, J. Rosset

Food Structure

The microstructure of portein/lipid gels produced by heat treatment of whey protein stabilized oil-in-water(O/W) emulsions was studied. Scanning electron microscopy as well as transmission electron microscopy was performed on glutaraldehyde/osmium tetroxide fixed, and critical point-dried samples. Microstructure analysis showed that in the case of homogenized O/W emulsions, extensive coating of the fat globule surface with coagulated protein led to a "cauliflower - like" structure. In such gels, uncoated fat globules having smooth surfaces were not present. This specific microstructure was not obtained with protein/lipid gels in which whey protein was added in the continuous phase and mixed with a O/W …

Image Analysis Of The Fat Dispersion In A Comminuted Meat System, Peter A. Koolmees, Piet C. Moerman, Monique H.G. Zijderveld

Food Structure

In a series of experiments on a comminuted meat system, image analyses were conducted to quantify changes in structure as affected by polyphosphate, fat level, and chopping time and temperature. Four batches of comminuted meat were investigated which contained neck beef, pig head meat, rino, ice, salt (2%), fat at a level of either 27 or 40%, and polyphosphate at a level of either 0 or 0. 5%. Structural changes in different stages of comminution coincided with a shift in size distribution, shape factor, density and area percentage of fat particles. The density of the protein matrix (matrix defined as …

Vacuole Formation In Wheat Starchy Endosperm, D. B. Bechtel, A. Frend, L. A. Kaleikau, J. D. Wilson, P. R. Shewry

Food Structure

The formation of vacuoles in wheat (Triticum aestivum cv. Highbury) starchy endosperm cells was studied using electron microscopy. Some vacuoles were always present, even in the coenocytic cytoplasm. The first formed endosperm cells were highly vacuolated, but became filled with cytoplasm as they grew older. Various-sized pieces of cytoplasm were found in vacuoles of developing endosperm cells, probably as a result of autophagic sequestration. The membranes of the autographic vacuoles appeared to originate from the rough endoplasmic reticulum and from extensions of already-formed vacuoles. Autographic activity was confirmed by localizing the hydrolytic enzyme acid phosphatase within the vacuoles. The rough …

Use Of Image Analysis To Predict Milling Extraction Rates Of Wheats, A. D. Evers, R. P. Withey

Food Structure

Image analysis of grain morphological characteristics was examined as a possible means of predicting extraction rates of a wide variety of wheat types.

Two elevations of grain were examined and measured for the top view whole grains were used, while for the lateral view grains were sagittally bisected in the plane of the crease. Extraction rate was assessed on laboratory mills and expressed as flour yield.

Milling extraction rate correlated with one shape factor with a coefficient of 0.78. Inclusion of a second factor in a stepwise regression increased the correlation coefficient to 0.925.

No satisfactory predictor of extraction rate …

Effect Of Heating To 200 C On Casein Micelles In Milk: A Metal Shadowing And Negative Staining Electron Microscope Study, V. R. Harwalkar, Paula Allan-Wojtas, Miloslav Kalab

Food Structure

Milk was heated to 200 C for 3 min in sealed inverted-Y-shaped glass vials and reacted with a glutaraldehyde solution at that temperature. Electron microscopy of the metal-shadowed and negatively stained samples revealed that casein micelles in the milk did not disintegrate extensively at the high-temperature used but, rather, became enlarged. Some of them were found to be either clustered or distorted.

A Method For Light And Scanning Microscopy Of Drought-Induced Damage Of Resting Peanut Seed Tissue, Clyde T. Young, William E. Schadel

Food Structure

Tissue damage creates numerous problems for the microscopic examination of resting peanut (Arachis hypogaea L. cv . Florunner) seed physical structure. This paper presents a method to deal with specific problems encountered in light microscopy (LM) and scanning electron microscopy (SEM) of drought - induced damage of peanut tissue . Major findings include: (1) improved SEM imaging through reduction of charging by increasing coating thickness from 25 nm to 30 nm; (2) improved stain affinity for LM tissue preparations by decreasing osmium tetroxide fixation time from 2 hours to 1 hour; and (3) im proved tissue fixation for LM and …

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

Cheese Industry Conference

No abstract provided.

Direct Selling Is A Plus For Cattle Producers, P G. Frapple

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

The aim when marketing cattle is to maximise the net return with the minimum level of risk. To do this a producer needs an accurate description of the stock for sale and information on the likely gross returns and costs of selling through the different marketing systems.

Since producers' selling costs and processors' buying costs are lower in direct sales, it is more likely that net returns from direct delivery will be higher.

Effect Of Electrical Charge On Attachment Of Salmonella Typhimurium To Meat Surfaces, James S. Dickson, John D. Crouse

James S. Dickson

Treating tissue with electrical current was found to affect both the initial attachment and total numbers of attached Salmonella typhimun’unl to meat tissues. When lean tissue was attached to the positive terminal of the power supply operating at 50 volts/125 mA DC, the total numbero f attachedc ells increasedT. hcrc was no effect when the samples were attached to the negative terminal. There was a significant (PcO.05) effect on the percentage of strongly attached bacteria with an increase in treating time. Electrical current was found to increase the percentage of strongly attached cells immediately after the current was applied.

Effects Of Nisin On Growth Of Bacteria Attached To Meat, James S. Dickson, K. T. Chung, J. D. Crouse

James S. Dickson

Nisin had an inhibitory effect on gram-positive bacteria (Listeria monocytogenes, Staphylococcus aureus, and Streptococcus lactis) but did not have an inhibitory effect on gram-negative bacteria (Serratia marcescens, Salmonella typhimurium, and Pseudomonas aeruginosa) attached to meat. Nisin delayed bacterial growth on meats which were artificially inoculated with L. monocytogenes or Staphylococcus aureus for at least 1 day at room temperature. If the incubation temperature was 5 degrees C, growth of L. monocytogenes was delayed for more than 2 weeks, and growth of Staphylococcus aureus did not occur. We also found that the extractable activity of nisin decreased rapidly when the meats …

Cell Surface Charge Characteristics And Their Relationship To Bacterial Attachment To Meat Surfaces, James S. Dickson, M. Koohmaraie

James S. Dickson

Cell surface charge and hydrophobicity of Bacillus subtilis, Escherichia coli O157:H7, Listeria monocytogenes, Salmonella typhimurium, Serratia marcescens, Staphylococcus aureus, and Staphylococcus epidermidis were determined by hydrocarbon adherence, hydrophobic interaction, and electrostatic interaction chromatography. Surface charge and hydrophobicity were compared with the initial attachment values and rates of attachment of the bacteria to meat surfaces. There was a linear correlation between the relative negative charge on the bacterial cell surface and initial attachment to lean beef muscle (r2 = 0.885) and fat tissue (r2 = 0.777). Hydrophobicity correlated well with attachment to fat tissue only. The relative hydrophobicity of each bacterium …

Menu, 1989, Gallagher's Boxty House

Gallagher's Boxty House

No abstract provided.

Enjoy Yeast Breads, Elna Miller, Georgia Lauritzen

All Archived Publications

No abstract provided.

Food Preservation--Plan Ahead, Marilyn B. Noyes, Jean Alder

All Archived Publications

No abstract provided.

Electron Microscopic Localization Of Cholesterol In Bovine Milk Fat Globules, Robert W. Martin Jr.

Food Structure

An electron microscopic method designed for the detection of cholesterol in milk fat was evaluated for reliability. This method is based on the incubation of cream from raw milk with fillipin (a polyene antibiotic) which has a specific affinity for cholesterol followed by freeze fracturing and electron microscopic examination of fat globules. Cholesterol was localized within the membrane and the triglyceride core of milk fat globules. Cholesterol was highly organized within membrane portions and less organized within triglyceride portions of milk fat globules. The configuration of localized cholesterol was similar to configurations reported for plasma membranes.

Microstructure And Texture Of Meat Emulsions Supplemented With Plant Proteins, Allan T. Paulson, Marvin A. Tung

Food Structure

A model meat emulsion system was used to evaluate the effects of cooking time and temperature on texture, microstructure and cook stability of meat emulsions containing soy or canola protein isolate. The plant proteins were incorporated either dry or rehydrated at replacement levels of 33.3% and 66.7% of the meat protein, and the emulsions were cooked at 70 or 95 C tor 25 or 50 min. Texture of the cooked emulsions was assessed by an instrumental texture profile analysis (TPA) using an lnstron tester . Analysis of TPA and stability data revealed several complex Interactions between experimental variables; however, level …

Effects Of Protein Concentration In Ultrafiltration Milk Retentates And The Type Of Protease Used For Coagulation On The Microstructure Of Resulting Gels, Dragoljub D.J. Gavaric, Marijana Caric, Miloslav Kalab

Food Structure

Milk retentates (35~ total solids, 13~ protein) obtained by ultrafiltration were diluted with the permeate to 3 . 2, 5.0, 6.5, 10.0, and 13.0% protein and coagulated using conrnerc1al proteases. Rennet or one of microbial proteases isolated from Bacillus potymlxa , Endothla parasfttca, Mucor mtehel, or Mucor pusfllus were used . Coagulation times were decreased with the Mucor proteases as the protein concentrations in the retentates were increased but the coagulation times were increased with B. potymlxa and f. parasltlca proteases under similar conditions . Firmness was higher in gels made from homogenized retentates than from nonhomogenized retentates of the …