Food Science Commons^™

The Skinned Fiber Technique As A Potential Method For Study Of Muscle As A Food, R. G. Cassens, T. J. Eddinger, R. L. Moss

Food Structure

Skeletal, smooth and cardiac muscle cells can be skinned by physical means or a variety of chemical techniques. The skinned fibers have been used to study the molecular mechanisms of contraction and the regulation of contraction by ca++. Skinned fiber preparations are also useful for study of muscle as a food. For example, it is now possible to determine fiber type of skinned fibers following study of their physical properties.

Microstructure Of Mealy And Vitreous Wheat Endosperms (Triticum Durum L.) With Special Emphasis On Location And Polymorphic Behaviour Of Lipids, A. Al Saleh, D. Marion, D. J. Gallant

Food Structure

Dark inclusions observed in osmiophilic zones, already described in mature wheat endosperm using transmission electron microscopy, were confirmed by freeze-fracture electron microscopy to be lipids. The polar lipids (glycolipids, phospholipids, free fatty acides, monoglycerides) were organized in a liquid crystalline phase. The reversed hexagonal or HII phase should be the main lattice which might arise from the transition of lipids present in membranous structures as a lamellar phase. This transition was caused by dehydration occurring during maturation. It is suggested that the water-dependent lamellar hexagonal phase transitions are of considerable importance in cereal food technology.

Features Of Food Microscopy, D. F. Lewis

Food Structure

The value of food microscopy is judged by its practical application to food handling. Hence microscopists must explain the relevance of their findings to food technologists. The food microscopist has to deal with materials that are particularly difficult to prepare for microscopy because they often contain high levels of fat, air, sugar, salt, starch or acid. Sometimes the methods used are unorthodox and could be regarded as questionable by microscopists in more traditional disciplines. This paper considers the relationship between food microscopists, food technologists and other microscopists. An approach to interpretation of images is based on the following features. 1) …

Texture And Microstructure Of Soybean Curd (Tofu) As Affected By Different Coagulants, J. M. Deman, L. Deman, S. Gupta

Food Structure

The coagulating properties of five coagulants and the nature of the curd obtained from soymilk was investigated . Viscosity changes during coagulation were studied using a Namctrc Vibrating Sphere Viscometer and texture measurements were made by compression and computer assisted analysis. pH and amount of solids in the whey were determined. The microstructure of the tofu was examined by sca nning electron microscopy. It was observed that CaCI2.2H20 and MgCI2.6H20 coagulaled the milk in stantl y while CaS04 .1/2H20. glucono delta l a~tonc (GOL) and MgS04 .7H20 acted comparatively slowly. The t exture of the curd was greatly influenced by …

Mucilage In Yellow Mustard (Brassica Hirta) Seeds, I. R. Siddiqui, S. H. Yiu, J. D. Jones, M. Kalab

Food Structure

Release of mucilage from yellow mustard (brassica hirta, also known as Sinapis alba) seed coats (hulls) was studied by optical and scanning electron microscopy. Micrographs were obtained of the mucilage which had exuded from briefly moistened seeds and dried subsequently in the form of small droplets on the seed surface.

The mucilage collected from the seed surface and mucilage isolated on a larger scale from seed hulls was hydrolyzed with sulfuric acid and the hydrolyzates were analyzed for sugar composition. Galactose, glucose, and galacturonic acid were found to be major components and mannose, arabinose, xylose, and rhamnose were minor components. …

The Development Of Structure In Whipped Cream, B. E. Brooker, M. Anderson, A. T. Andrews

Food Structure

Interfacial changes occurring during the formation of whipped cream were followed using transmission and scanning electron microscopy. During the initial stages of whipping, air bubbles were stabilized by adsorbed 8-casein and whey proteins with little involvement of fat globules. The adsorption of fat to a i r bubbles occurred ~.then the globule membrane coalesced with the protein a ir-water i nterface . As a res ult, fat was brought into direct contact with air but only rarely did it spread at the ai.r-fat interface. The crosslinking of fat globules adsor bed t o adjacent air bubbles by chains of coalesced …

The Structure Of Gluten Gels, A. M. Hermansson, K. Larsson

Food Structure

This paper reports on a combined electron microscopy and X-ray diffraction study of gluten gel, in which conventional gluten, a delipidized gluten sample and a storage protein fraction obtained by salt-fractionation were used. It can be concluded that the gluten gel is a continuous phase of densely packed protein units. Other structural components such as air ce lls, lipid droplets, liposomes, fiber residues, starch granules etc. are dispersed in the continuous matrix. The space available for water is strictly limited in the continuous phase due to the dense packing of protein molecules. Water that is not completely separated from the …

Mechanical Properties Of Cheese, Cheese Analogues And Protein Gels In Relation To Composition And Microstructure, M. L. Green, K. R. Langley, R. J. Marshall, B. E. Brooker, A. Willis, J. F. V. Vincent

Food Structure

Samples of commercial Cheddar cheese, experimental Cheddar cheeses made from heated, ultrafiltration-concentrated mllks, processed cheese analogues and whey protein gels of defined composition were examined microscopically and some fracture and deformation properties were determined. Surfaces of cheese prepared by critical point drying and those examined frozen were comparable in microstructure. As the concentration factor of the milk used for experimental c heesemaking increased, the cheese became more resistant to reversible deformation, the work required to cut with a wire or break wf th a hammer increased and the microstructure showed that the protein matrix was coarser. The force to deform …

Relationship Between Microstructure And Susceptibility To Syneresis In Yoghurt Made From Reconstituted Nonfat Dry Milk, V. R. Harwalkar, Miloslav Kalab

Food Structure

Increase in the density of protein matrices i n yoghurt samples conta ining 10 to 30% total milk sol ids was studied by scanning electron micros copy and was corr e lated with a decrease in syneresis. Casein particles which formed chains and clusters in the protein matrix were largest in the 10% total solids yoghurt and their dimensions were decreased as the total solids contents were increased. This observation was confirmed by transmission electron microscopy of thin sections. An attempt has been made to explain the discrepancy between results on syneresis obtained by a drainage and a centrifugation method …

Simple Method To Demonstrate Radiation-Inducible Radiation Resistance In Microbial Cells, S. T. Tan, R. B. Maxcy

Department of Food Science and Technology: Faculty Publications

A simple method for detection of radiation-inducible radiation resistance was developed by irradiating aliquots (0.01 ml) of cell suspension on agar plates. Part of each experimental plate was subjected to an induction treatment, and subsequent radiation resistance was compared with that of untreated cells on the same plate. The UV radiation resistance of a Micrococcus sp. was increased approximately 1.6 times by an induction treatment. This simple procedure of irradiating cells in a "fixed" position on agar avoided washing, centrifugation, and cell enumeration required in traditional methods.

Azolla (Azolla Microphylla Kaulfuss) As Nitrogen Source And Weed Suppressant In Drill-Seeded And Transplanted Lowland Rice, Mansor Bin Puteh

Graduate Student's Output

No abstract provided.

Ua37/13 Plants Used By The Prehistoric Indians Of Kentucky, Chuck Crume

Faculty/Staff Personal Papers

No one knows exactly when the Indians first entered the area we now call Kentucky, but there is an approximation. Archeologists have found evidence of Clovis camps and living sites in the state (9,000 to 12,000 B.P.), This would have been during the Paleo Stage, toward the end of the last ice age. The climate of the area would have been much cooler then. The selection of plants and animals would also have been different than those found in modern times.

Paleo Indians used plants for food, utility and medical uses. It seems that plant use during this period is …

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 …

Galactose Transport In Streptococcus Thermophilus, Robert W. Hutkins, Howard A. Morris, Larry L. Mckay

Department of Food Science and Technology: Faculty Publications

Although Streptococcus thermophilus accumulated [¹⁴C]lactose in the absence of an endogenous energy source, galactose-fermenting (Gal⁺) cells were unable to accumulate [¹⁴C]galactose unless an additional energy source was added to the test system. Both Gal⁺ and galactose-nonfermenting (Gal^-) strains transported galactose when preincubated with sucrose. Accumulation was inhibited 50 or 95% when 10 niM sodium fluoride or 1.0 mM iodoacetic acid, respectively, was added to sucrose-treated cells, indicating that ATP was required for galactose transport activity. Proton-conducting ionophores also inhibited galactose uptake, although N,N'-dicyclohexyl carbodiimide had no effect. The results suggest …

Soybean Oil Is Not Allergenic To Soybean-Sensitive Individuals, Robert K. Bush, Steve L. Taylor, Julie A. Nordlee, William W. Busse

Department of Food Science and Technology: Faculty Publications

We have previously demonstrated that peanut oil is not allergenic to peanut-sensitive individuals. Seven soybean-sensitive patients were enrolled in a double-blind crossover study to determine whether ingestion of soybean oil can induce adverse reactions in such patients. All subjects had histories of systemic allergic reactions (urticaria, angioedema, wheezing, dyspnea, and/or vomiting) after soybean ingestion and had positive puncture skin tests with a 1:20 w/v glycerinated-saline whole soybean extract. Sera from six of the seven subjects were tested by RAST assay for the presence of specific IgE antibodies to soybean allergens. All patients had elevated levels of serum IgE antibodies to …

Modifying Lamb/Mutton Flavors In Processed Meat Products By Smoking, Curing, Spicing, Starter Cultures And Fat Modifications. Investigating The Use Of The Technicon Infraalyzer 400r As A Rapid Method For Proximate Analysis, Chima I. Osuala

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mutton meat was tested in different products in order to obtain prototype products in which mutton can effectively be used without the objectionable mutton off flavor. Mutton flavor reduction was achieved in the processed meat products by: (a) lowering mutton fat to a level of 10% or less, (b) using spices, smoking and/or curing, (c) substituting fat from beef or pork for mutton fat, and (d) the action of microbial starter cultures. Four taste panel sessions were set up to rate these products against an all beef or all pork control for consumer acceptability. Taste panel results indicate that flavor …

Effect Of Iron On Residual Nitrite Level In Ground Pork And Model Systems, Changmin Kim

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effects of iron, temperature, and presence of botulinal spores or sodium ascorbate on depletion of nitrite level were determined in meat and model systems. Higher temperature and presence of botulinal spores definitely increased nitrite depletion in a meat system. Added hemoglobin also significantly increased nitrite depletion, while ferrous iron and ferric iron did not significantly decrease nitrite level in a meat system. High temperature and presence of sodium ascorbate increased nitrite depletion in a model system. Only ferrous iron significantly decreased nitrite level in the absence of ascorbate, while ferric iron, heme iron, and ferritin iron did not decrease …

Effect Of Proteolytic Activity Of Streptococcus Cremoris On Cottage Cheese Yield, Gary W. Stoddard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Using proteinase negative variants of Streptococcus cremoris UC310 or UC320 to manufacture cottage cheese, theoretical yields were increased 1.97% and 1.56% respectively when compared to the theoretical yields of the proteinase positive parents. Yield differences were strain dependent and differences between positive and negative variants were not manifest with strains of UC73 and UC97. It was necessary to produce bulk culture using pH control and to add sufficient nitrogenous stimulant to provide carry-over stimulant into the cheese milk. All cultures examined developed normally even when the bulk medium contained a blend of 5% yeast extract and casein hydrolysate. It was …

Iron Requirement Of Clostridium Botulinum Type A And Characterization Of Iron-Sulfur Proteins In Nitrite Treated And Untreated Botulinal Cells, Divya Shree A. Reddy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effect of added iron on the growth of Clostridium botulinum type A in a chemically defined medium was studied. Growth of C. botulinum was supported by an iron level of 0.05 ug/ml with maximum growth observed at a level of 3 ug iron/ml.

Electron paramagnetic resonance (EPR) studies were conducted to detect the presence of iron-sulfur centers and iron-nitric oxide complexes in untreated and nitrite treated cell-free extracts of C. botulinum type A. Untreated extracts of C. botulinum exhibited EPR signals in the oxidized and reduced states characteristic of a "HiPiP-type" iron-sulfur center (g=2.02) in the oxidized state and …

Effects Of Bulk Starter Media And Proteolytic Lactic Streptococci On Protein Loss In Cheddar Curd Manufacture, Steven A. Winkel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effects of whey-based and milk-based starter media, and low concentrations (0.02% each) of citrate, phosphate and calcium upon various milk coagulation properties were measured. Samples inoculated with milk-based starter medium had shorter coagulation times, faster rate of curd formation, and greater final curd firmness than those inoculated with externally neutralized whey-based starter. Starter medium treatment was statistically interacted with calcium for coagulation time and rate of curd formation. Citrate addition caused longer coagulation times, slower rates of curd formation, and weaker final coagula. Citrate interacted with calcium and phosphate for several of the parameters measured. Addition of phosphate did …

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 …

Estimates Of Soil Solution Ionic Strength And The Determination Of Ph In West Australian Soils, P. J. Dolling, G. S.P. Ritchie

Food Science and Nutrition

The average ionic strength of 20 West Australian soils was found to be 0.0048. The effects of three electrolytes (deionized water, CaCl₂ and KNO₃), three ionic strengths (0.03, 0.005 and soil ionic strength at field capacity, I_s) and two soil liquid ratios (1:5 and 1:10) on the pH of 15 soils were investigated. pH measurements in solutions of ionic strength 0.005 differed the least from measurements made at I_s. The differences that occurred in comparisons with distilled water or CaCl₂ of ionic strength 0.03 (0.01 M) were much greater (≥0.4 pH …

The Role Of Organic Matter In Soil Acidification, G. S.P. Ritchie, P. J. Dolling

Food Science and Nutrition

The pH and buffer capacity of two soils increased or remained constant after incubation with different amounts of plant material (lucerne cham at field capacity and when air dry. For both soils, the pH changes were greater at field capacity, whereas the buffer capacities were independent of the water treatments. The pH changes observed could be explained in terms of the organic anion concentration of the plant material. The results indicate that the initial soil pH and the anion concentration (i.e. the per cent dissociation of soluble organic acids when released into the soil) determine the acidifying effect of organic …

Ultrastructural Studies On The Cultivation Processes And Growth And Development Of The Cultivated Mushroom Agaricus Bisporus, D. A. Wood, G. D. Craig, P. T. Atkey, R. J. Newsam, K. Gull

Food Structure

Scanning electron microscopy (SEM) , transmission electron microscopy and light microscopy have been used to study various processes in the cultivation of the edible mushroom Agaricus bisporus . Mushrooms are cultured on composted wheat straw. The microbial degradation processes during composting have been visualised by TEM and SEM and correlated with microbiological studies . Various modes of attack by the microorganisms on the plant cell walls can be seen. Most rapid degradation occurred on the cuticle and phloem and spread to other cell types. Microbial attack was found to be nonuniform between tissue types and individual cells. The mycelium of …

Fruit Canning Methods, Georgia C. Lauritzen

Archived Food and Health Publications

Publication gives instructions for canning various different types of fruit.

The Size Distribution Of Bovine Casein Micelles: A Review, C. Holt

Food Structure

This review considers the average size and size distribution of bovine casein micelles as measured by electron microscopy, light scattering and controlled pore glass chromatography, and the origin and biological function of the size distribution.

Recent work by electron microscopy has given average sizes in reasonable agreement with measurements on the same milk sample by light scattering . It is suggested that natural variations in averaqe micelle size and overestimation of micelle radii by light scattering methods as well as deficiencies in electron microscopical methodology were responsible for past discrepancies.

Electron microscopy and controlled pore glass chromatography provide evidence that …

Structure Of Coarse And Fine Fractions Of Corn Samples Ground On The Stenvert Hardness Tester, Y. Pomeranz, Z. Czuchajowska

Food Structure

Kernels from a pair of isogenic lines (with regard to hardness) and two commercial hybrids of dent corn (that varied in hardness) were ground on the Stenvert Hardness Tester and separated by sieving into coarse (>0.710 mm) and fine (<0.500 mm) fractions. The corn samples differed little in oil contents. The coarse particles from the hard corn samples were angular and sharp-edged; those from the soft corn samples were rounded. The yield of coarse particles was higher and they contained less oil in hard than in soft corn. Fine particles from all four corn samples had higher oil content than the coarse particles. Visual examination, observation at low magnification under a light microscope, and use of a scanning electron microscope revealed consistent differences in the extent and mode of corn kernel breakdown during grinding. Particles in the coarse fraction from hard kernels were to a large extent intact with little exposure of their contents. In the soft kernels, particles in the coarse fraction were broken extensively and their contents exposed. It is postulated that differences in the extent of mechanical breakdown and oil content are related to differences in shelf life of corn grits.

Relation Between Microstructure, Destabilization Phenomena And Rheological Properties Of Whippable Emulsions, W. Buchheim, N. M. Barfod, N. Krog

Food Structure

The structure of spray-dried whippable emulsions (toppings) containing different types of lipid surfactants, was investigated by electron microscopy using the freeze-fracture technique. The size distribution of the lipid particles within the powders varied with the type of the surfactant used. After reconstitution of the topping powders in water. a strong destabilization phenomenon took place to an extent depending on the type of the surfactant. Simultaneously a crystallization of coalesced lipid particles occurred along with an increase in viscosity of the emulsions. The degree of crystallization was measured by p-NMR. It has been concluded that these phenomena are closely related to …

Thermal Analysis Microscopy For The Study Of Phase Changes In Fats, J. M. Deman, A. N. Mostafa, A. K. Smith

Food Structure

An investigation was carried out using the Mettler FPBOO Thermosystem to study polymorphic transitions of several monoacid triglycerides and hydrogenated Canola oil. The system includes a central processing unit connected with a thermal microscopy hot stage that allows the measurement of heat flow to the scrnple . Scanning electron microscopy was also used to examine the same samples after osmium tetroxide fixation . The results obtained relate phase transitions occurring during heating and cooling with the morphology of the various crystal structures.

Ultrastructural Ultilization Of Plants By Herbivores, L. H. Harbers

Food Structure

Study of the patterns of ruminal digestion of forages enhances the nutritional knowledge of how specific plant tissues are digested and adds its own dimension by characterizing the specific cells and the complex interactions of ruminal microflora with those tissues. A common pattern of digestibility exists for mono- and dicotyledon leaves: mesophyll and phloem are degraded readily, and sclerenchyma slowly, whereas cuticle and the remaining vascular tissues are rarely utilized . Digestion of stems is limited to parenchymal tissues in monocotyledons and to cortex and parenchyma in dicotyledons. Epidermal silica and cuticle are undigestible and restrict microbial entrance. Calcium oxalate …