Food Science Commons^™

Identification Of Proteins And Complex Carbohydrates In Some Commercial Low-Fat Dairy Products By Means Of Immunolocalization Techniques, Barbara L. Armbruster, Nitin Desai

Food Structure

Macromolecular assemblies of proteins and hydrocolloids in low-fat dairy products contribute to the structure and texture of these foods. Immunolocalization techniques were used to identify B-lactoglobulin, casein, bovine whey proteins, and egg albumin in low-fat frozen desserts, reduced fat process cheese, and salad dressings. SimpJesse18 I 00 protein particles were examined and characterized by these methods and compared to naturally occurring protein structures in the low-fat foods. Hydrocolloid identification in low-fat salad dressing was accomplished by complexing cellulase and hemicellulase with colloidal gold and applying the probe as a pre-embedding step, on sections of embedded specimens or on material dried …

Scanning Electron Microscopy Studies Of A Typical Spanish Confectionery Product: "Xixona Turron", M. A. Lluch, M. J. Galotto, A. Chiralt

Food Structure

The microstructure of "Xixona turron" , a typical Spanish confectionery product, made with toasted almonds, sugar and honey, was elucidated, in order to confirm the nature of those physical changes occurring in its manufacturing process, which has not been previously studied. The effect of the major components of "Xixona turron" (oil, proteins and sugar) on its structural c!Jange was established. The initial oil suspension of sugar syrup drops and proteins undergoes a phase inversion , becoming an oil /water emulsion when hot, and a solid-like structure, when the aqueous sugar continuous phase solidifies at room temperature. In order to determine …

Distribution Of Aromatic Compounds In Coastal Bermudagrass Cell Walls Using Ultraviolet Absorption Scanning Microspectrophotometry, Nancy P. Ames, Roy D. Hartley, Danny E. Akin

Food Structure

The distribution of aromatic constituents, including lignin , in the leaf cell walls of "Coastal" hermudagrass (Cynodon dacrylon (L.) Pers.) was investigated using scanning ultraviolet (UV) microspectrophotometry. Leaf blade sections and individual tissue types were scanned at three wavelengths representing the absorbance maxima (318, 287 and 250 nm) of aromatic constituents present in bermudagrass leaves. The measured absorbance data were printed in a geometric arrangement to produce an image of the distribution and amount of aromatic constituents among and within cell wall types which vary in digestibility . Differences in absorbance were observed among cell wall types, among walls of …

Effect Of Chemical Modifications On The Stability, Texture And Microstructure Of Cooked Meat Batters, Andre Gordon, Shai Barbut

Food Structure

The effects of five chemical agents on the stability, texture and microstructure of cooked comminuted meat batters were studied. B-mercaptoethanol (/3-ME), hydrogen peroxide (H20~, ethylenediaminetetraacetic acid (EDT A), urea, and polyoxyetbylene sorbitan monooleate (fween 80) were used. The reduction of disulphide bonds by 8-ME or the oxidation of free sulphydryls by H20 2 prior to cooking did not affect liquid and fat losses during cooking as compared to the control (2.5% NaCI). However, texture profile analysis (fPA) showed that treatment with H20 2 resulted in a harder, more cohesive product than the control and ,8-ME treatments because a more fine-stranded, …

Effect Of Lactose And Protein On The Microstructure Of Dried Milk, V. V. Mistry, H. N. Hassan, D. J. Robison

Food Structure

Skim milk of approximately 3% total protein was ultrafiltered to 16.2% protein and 4.1 % lactose, and then diafiltered to reduce lactose to 2.1% and 0.9%. Total protein con ten t was maintained at approximately 17%. A ponion of the skim milk was condensed in a rising film evaporator to 14.7% protein and 15.7% lactose . All concentrates were spray dried at 120 to 125 °C inlet air temperature and 75 to 80 C outlet temperature using a rotary atomizer in a pilot plant spray dryer . Moisture content of the powders were 4.7 to 6.3% and lactose content ranged …

Cryo-Scanning Electron Microscopy Investigation Of The Texture Of Cooked Potatoes, J. T. Van Marle, A. C.M. Clerkx, A. Boekestein

Food Structure

The texture of steam-cooked potatoes was investigated by examining the fracture planes of four different cultivars, using cryo-scanning electron microscopy (cryo-SEM), which yielded a good preservation of the hydrated structures in potato tissue . For all cultivars , fracturing after steam -cooking took place between cells preferentially alongside the cell walls. However, textural difference appeared from the degree of intercellular contact, the cell shape and the appearance of cell surfaces. Cells in the fracture planes of firm potatoes had large intercellular contacts. In this case, most of the cells were flat and cell surfaces showed folds and cracks . For …

Physicochemical Properties Of Irradiation Modified Starch Extrudates, A. S. Sokhey, R. Chinnaswamy

Food Structure

Corn starch samples containing 0, 25, 50 and 70% amylose irradiated with -y -radiation dosages of 0 (native) , 5 , 10, 20 (containing 0, 2.5 or 5% potassium persulfate , hydrogen peroxide or eerie ammonium nitrate) or 30 kGy were extrusion cooked using a C. W. Brabender single-screw extruder at a barrel temperature of 140 °C, a screw speed of 140 rpm and 18% moisture content. Increasing irradiation dosages from 0 to 30 kGy gave consistently increased expansion ratios from 2.9 to 7.9 for 25% amylose starches and from 6.5 to 14.5 for 50% amylose starches, while the expansion …

Taking The Emu To Market, Paul Frapple, Ruth Hagan

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

Licensed, commercial emu farming in Western Australia is now five years old.

This year, 13,500 birds will be processed for their meat, skin and oil. Production has exceeded demand at prices which the industry considers fair because the industry is still developing marketd for these producys.

Without secure, long term markets, over-production will worsen as the turn-off in this State increases and emus become available from other Australian states and overseas.

The Department of Agriculture is assisting the industry to develop a viable industry.

Breeding Better Malting Barleys, Ross Gilmour, Allen Tarr, Stefan Harasymow

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

Development of new barley cultivars in Western Australia has substantially improved the grain yield and quality of the State's barley crop. This has increased returns to barley growers and enhanced Western Australia's reputation in export markets as a major supplier of barley for malting and feed.

The State exports more than 200, 000 t of malting barley, 60, 000 t of barley malt and 150, 000 t of feed barley each year.

The major challenge for the future is to develop new, high yielding cultivars with improved malting quality.

In this article, the authors discuss the achievements of the past; …

Characterization Of A Regulatory Network That Controls ΣB Expression In Bacillus Subtilis, Andrew K. Benson, William G. Haldenwang

Department of Food Science and Technology: Faculty Publications

The sigB operon of Bacillus subtilis encodes σ^B and three additional open reading frames (orfV, orfW, and orfX). Having previously mapped several mutations that alter the induction pattern of a σ^B-dependent promoter (ctc) to regions of cloned B. subtilis DNA which contain these three open reading frames, we directly tested the regulatory potential of orfV, orfW, and orfX by creating null alleles of each of these genes and examining the effects of the mutations, either singly or in pairs, on transcription of ctc and the sigB operon. …

How To Turn Your Kitchen Into A Lab!, Charlotte P. Brennand Ph. D.

Archived Food and Health Publications

Publication goes over the steps to a proper experiment and teaches how to do experiments in your own kitchen.

Drug Residues And Food Safety, Clell V. Bagley Dvm

Archived Food and Health Publications

Publication discusses drug residues in food animal products and food safety concerning drug residues.

Drug Use In Food Animals, Clell V. Bagley Dvm

Archived Food and Health Publications

Publication provides information on the safe use of drugs and antibiotics in food animals.

Food Handling Practices Among Independent-Living Elderly, Judith Dianne Mcdonough

Loma Linda University Electronic Theses, Dissertations & Projects

Food has long been recognized as a vehicle of disease transmission; there are more reported illness associated with the consumption of food than all other environmental factors combined. The handling and storage of food are potentially dangerous and demanding chores for those who may have the sensory losses associated with advancing age, fragile health, and limited resources.

Group-administered questionnaires on the knowledge, attitudes, and practices of food handling were given to 276 seniors, aged 55 to 90, from ten mobile home parks randomly selected from San Bernardino and Riverside counties. As an indicator of possible foodborne illness, the questionnaire asked …

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 WMMB's programs …

Intracellular Ph Effects In Lactic Acid Bacteria, Nancy L. Nannen, Robert W. Hutkins

Department of Food Science and Technology: Faculty Publications

The objectives of this research were to determine the effect of lactic acid and low pH on the intracellular pH in three species of lactic acid bacteria. A pH gradient (intracellular pH minus the extracellular pH) of .9 to 1.4 pH units was achieved by several strains of lactic acid bacteria, including Streptococcus thermophilus 19258 and 573, Lactococcus lactis ssp. lactis C2, and Lactococcus lactis ssp. cremoris HP during log phase of growth in various media. A noticeable decline of the pH gradient occurred at an internal pH of 5.5 to 6.0. In late stationary phase, the pH gradient was …

Proton-Translocating Adenosine Triphosphatase Activity In Lactic Acid Bacteria, Nancy L. Nannen, Robert W. Hutkins

Department of Food Science and Technology: Faculty Publications

Streptococcus thermophilus 19258 and 573, Luctococcus luctis ssp. lucris C2, Lactococcus luctis ssp. cremoris HP, and Luctobucillus cusei 685 were grown in various media and assayed for protontranslocating ATPase (H⁺-ATPase) activity. The H⁺-ATPase was extracted from the membrane fractions of protoplasted cells using a French pressure cell, and activity was measured by the release of inorganic phosphate from ATP. The pH optima for the H⁺-ATPase, assayed in vitro, were 7.5 for S. thermophilus and Lactococcus luctis ssp. cremoris HP and 5.0 for Lactobacillus casei 685. In contrast, for cells grown in batch …

Bulletin No 4225 - Dairying In Western Australia, Dean Maughan

Bulletins 4000 -

Dairying in Western Australia is a small though very efficient industry. In 1989/90, 480 dairy farmers produced 266 million litres of milk for an estimated return of $84 million. The retail value of milk and dairy products was estimated to be $250 million making dairying a very significant industry in the south-west of Western Australia.

Anticarcinogenic, Antitumor, And Antifungal Properties Of Allium Sativum (Garlic), Padma P. Tadi

Loma Linda University Electronic Theses, Dissertations & Projects

In this study the antimutagenic/anticarcinogenic, immune enhancing, antitumor and antifungal effects of a crude extract and organosulfur compounds of garlic were determined. Diallyl sulfide (DAS), and ajoene each at 100 /xg/ml, and garlic extract (GE, 12.5 mg/ml) inhibited rat liver 9000 X g supernatant (S- 9) dependent mutagenesis in Salmonella typhimurium TA100 induced by either aflatoxin B1 (AFB^ or benzo[a]pyrene (B[a]P). The garlic compounds were shown to inhibit the binding of [³H]AFB₁ to calf thymus DNA and the formation of specific AFB_1-DNA adducts. These effects on mutagenesis and DNA binding correlated with an inhibition of …

Meat Effects On Nonheme Iron Absorption, Yunji Kim

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Studies were undertaken to investigate if gastric acidity and iron chelation to a meat component enhance nonheme iron absorption. Cereal meals, with and without added proteins, were gavaged into iron-deficient rats. The role of iron chelation was investigated by adding sodium phytate, an iron chelator implicated with decreased iron absorption, to the meals. The role of gastric acidity was investigated by treating the rats with cimetidine, which inhibits gastric acid production. In rats with normal acid production, beef, pork and chicken enhanced iron absorption when phytate had been added to the meals, suggesting a role for chelation in meat enhancement …

Rapid Determination Of Milk Components And Detection Of Adulteration Using Fourier Transform Infrared Technology, Ivan Von Mendenhall

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Absorption bands responding to changes in fat, protein, and lactose concentrations in milk were determined. The effects of milk fat variation and lipolysis on the infrared spectrum were studied.

Absorbances from 1283 to 1100 cm^-1 correlated with fat, protein, and lactose concentration and showed a low response to milk fat variation and lipolysis. A Fourier transform infrared spectrometer equipped with an attenuated total internal reflectance cell was calibrated using these absorption band s, partial least squares statistics, and milk samples from herds in Minnesota. When the fat, protein, and lactose concentrations in these samples were predicted, the standard deviations …

Factors Affecting Moisture Distribution In 290-Kilogram Stirred-Curd Cheddar Cheese Blocks, Robert S. Reinbold

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this dissertation was to study factors affecting moisture distribution in 290-kilogram stirred-curd Cheddar cheese blocks cooled in stainless steel hoops. Uneven moisture distribution within blocks may create cheese with variable texture and flavor, which can be extremely costly to the producer. The effects of temperature, pH, and vacuum treatment on moisture distribution were investigated. Temperature, pH, moisture, and pressure profiles were presented. Also, comparisons were made between temperature profiles of 290- kilogram stirred-curd Cheddar cheese blocks cooled in stainless steel and in plywood hoops, as well as between temperature profiles of 66-kilogram Swiss cheese blocks cooled in …

Determining The Validity Of Methods Used In Meat Iron Analysis, Padmashri Ummadi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The validity of the Homsey method for heme iron, modified Schricker and sodium pyrophosphate extraction methods for nonheme iron and atomic absorption spectrophotometry (AAS) and ferrozine methods for total iron were determined using spikes of hemoglobin, ground beef baked to different degrees of doneness, proportional beef liver:catfish mixtures and National Institute of Science and Technology reference materials.

The mean spike recoveries of 0.01g and 0.02g Hb in raw beef and raw chicken samples were 96.7% of the heme iron for the Homsey method, 97.9% of the total iron for the ferrozine method, and 85.7% of the total iron for the …

Effects Of Heat Treatment Of Ultrafiltered Milk On Its Rennet Coagulation Time And On Whey Protein Denaturation, Bashir H. Yousif

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this research was to determine the effects of heating (including heating to ultra-high temperatures) homogenized ultrafiltered whole and skim milks on whey protein denaturation and milk's subsequent rennet coagulation properties: coagulation time, curd firmness, and microstructure.

Whole and skim milk samples were ultrafiltered using a spiral wound ultrafiltration membrane system. Samples were preheated to 72°C for 58 s, held for 8 s then heated to 72, 89, 106, 123, or 140°C for more than 97 sand held for 4 s. The milk was then cooled to 60°C and homogenized, further cooled to 30°C, packaged into 120 ml …

Survival Of Lactobacillus Acidophilus And Bifidobacteria Bifidum In Ice Cream For Use As A Probiotic Food, Sharareh Hekmat

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ice cream mix (12% fat, 11% milk solids nonfat, 12.5% sugar, and 4.5% corn syrup solids) was fermented with Lactobacillus acidophilus and Bifidobacterium bifidum. Half of the mix was heat treated at 82°C for 30 minutes and cooled to 40-41°C. The other half was warmed to 40-41°C and inoculated with the starter cultures. Both were made into ice cream and stored at -29°C. Survival of L. acidophilus and B. bifidum and of ẞ-galactosidase activity were monitored during 17 weeks of frozen storage. Reinforced clostridial medium was used to enumerate culture bacteria. Colony counts, after fermentation, for both L. acidophilus …

An Automated Reflectance Color Meter Instrument For Microbiological And Enzymic Assays, Tsz-Ching Yuan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The development of an automated instrument employing reflectance colorimetry was described. Several models were designed, assembled, and programmed to perform microbial and enzymic tests automatically. Samples were prepared manually or automatically by a Zymate™ II robot. These samples were incubated during the tests to maintain an optimum temperature for reactions and microbial growth. During incubation, color changes of appropriate indicator dyes in the sample/reagent mixtures were measured intermittently, recorded, and compared to previously defined end points. The computer-controlled instrument received data that related time of color changes with the initial numbers of microorganisms or the enzyme activity of the samples. …

Lactose Uptake Driven By Galactose Efflux In Streptococcus Thermophilus: Evidence For A Galactose-Lactose Antiporter, Robert W. Hutkins, Carina Ponne

Department of Food Science and Technology: Faculty Publications

Galactose-nonfermenting (Gal^-) Streptococcus thermophilus TS2 releases galactose into the extracellular medium when grown in medium containing excess lactose. Starved and de-energized Gal^- cells, however, could be loaded with galactose to levels approximately equal to the extracellular concentration (0 to 50 mM). When loaded cells were separated from the medium and re-suspended in fresh broth containing 5 mM lactose, galactose efflux occurred. De-energized, galactose-loaded cells, re-suspended in buffer or medium, accumulated ['4C]lactose at a greater rate and to significantly higher intracellular concentrations than unloaded cells. Uptake of lactose by loaded cells was inhibited more than that by unloaded …

Soil Tests For Aluminum Toxicity In The Presence Of Organic Matter: Laboratory Development And Assessment, M. G. Whitten, G. S.P. Ritchie

Food Science and Nutrition

Al toxicity in plants is related to the activity of Al³⁺ and Al-hydroxy monomers in the soil solution, whereas Al complexed with ligands such as fluoride (F), sulphate (SO₄^2-), and oxalate is not toxic. Estimation of toxic Al relies on measurement of “labile”; Al after short contact times with colorimetric reagents or cation-exchange resins. However, shifts in equilibrium may result in non-toxic forms of Al reacting with the complexing agent or resin.

A series of laboratory experiments tested the degree to which labile Al is related to Al³⁺ in simplified media and compared methods of …

Calcium Chloride Extractable Cadmium As An Estimate Of Cadmium Uptake By Subterranean Clover, M. G. Whitten, G. S.P. Ritchie

Food Science and Nutrition

Cadmium (Cd) may accumulate in soils which have been regularly fertilized with phosphate fertilizers which contain Cd originating in rock phosphate. Soil was taken from three sites in the wheatbelt of Western Australia which were estimated to have received different amounts of phosphate fertilizer over the past decade. The pH was adjusted with dilute HCl or CaCO₃. No Cd was added experimentally. The concentration of Cd in the whole tops of Trifolium subterraneum cv Mt Barker grown in a glasshouse pot experiment increased from 0.2-0.8 µg g^-1 dry wt at pH 6.6-6.9 (1:5 0.01 M CaCl …

Physicochemical And Macromolecular Properties Of Starch-Cellulose Fiber Extrudates, R. Chinnaswamy, M. A. Hanna

Food Structure

Three different pure cellulose fibers (James River Corporation, NJ) with lengths of 22, 60 and 110 pm were used at 1, 2, 4, 6, 8 and 10% concentrations with normal corn starch. The fiber-starch mixtures were extruded (C.W. Brabender Laboratory Extruder) at moisture contents of 14, 18 and 22% (db), 140°C barrel temperature and 140 rpm screw speed. The expansion ratio of the starch-fiber extrudates varied from 5.0 to 13.3. The maximum expansion ratio of 13.3 was obtained with 2%-60 mm fiber and 14% (db) moisture content. Increasing fiber concentration and moisture content generally reduced the expansion volumes. Water solubility …