Food Science Commons^™

Heat Stability Of Residual Milk Clotting Enzymes In Cheese Whey, James Winter Duersch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Eliminating calcium chloride and replacing whole casein with k-casein eliminated clouding and sharpened diffusion boundaries in casein-agar gels used for the estimation of residual milk clotting enzymes in curd and whey. It also eliminated the need for a highly purified calcium-free agar. The substrate contained .54 percent k-casein, 3.6 percent sodium acetate, .73 percent bacto-agar and 95.13 percent water. The pH was adjusted to 5.9 with .1N hydrochloric acid.

Proteases derived from Mucor pusillus var Lindt, Mucor Miehei and Endothia parasitica, as well as rennet, procine and bovine pepsins were used at recommended levels to set milk for …

Quantitation Of Aliphatic Aldehydes In Rancid Turkey Meat Using A Substituted Hydrazone, Stanley J. Andrews

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Many objective chemical tests have attempted to correlate with organoleptic evaluation of oxidative rancidity. Major chemical tests used to detect oxidative rancidity of lipids measure nonvolatile high molecular weight carbonylic substances which make no considerable contribution to rancid flavors. High molecular weight carbonyls are present at much greater concentrations than volatile low molecular weight carbonyls. Peroxides and other unknown substances also react in these chemical tests to give at best an empirical evaluation. A 3-methyl-2-benzothiazolinone hydrazone chemical test is proposed which corrected some deficiencies of earlier procedures, and was correlated with organoleptic evaluation of rancid turkey samples. The proposed test …

The Role Of Zinc In Insulin Metabolism In The Pancreas Of The Rat, Chih-Chi Liaw

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A series of in vitro trials have been conducted to determine what relationship exists between zinc and the insulin mechanism.

There were no significant differences of the zinc contents in total pancreases excised from the rats thirty minutes after the intraperitoneal glucose dose or from the non-dosed controls. When pancreases were cut into three pieces, and treated in three ways: Incubated without glucose (IWG) followed by isolation of the islets; incubated with glucose (IWG) followed by isolation of the islets; islets were isolated, then incubated with glucose (IWG). The zinc content in the islets was significantly higher (p < 0.01) in the first group than the others.

The insulin …

Some Effects Of Mechanical Deboning On The Composition And The Bioavailability Of Protein And Iron In Turkey Frame Meat, Lowell C. Allred

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Meat was obtained from a single daily lot of turkey frames by mechanically deboning with a Beehive AU 4171 deboner and by hand deboning. The meat was analyzed for protein, fat, moisture, ash, iron, calcium, and 19 amino acids. Mechanically deboned turkey had 68 percent more ash, 74 percent more iron, and nine times more calcium than the hand deboned turkey meat. Other constituents were about equal in the two products. Protein bioavailability tests, including protein efficiency ratio, biological value, net protein utilization, and nitrogen efficiency for growth, did not reveal significant differences between mechanically deboned and hand deboned turkey. …

Evaluation Of A Vapor Pressure Osmometer For Determination Of Added Water In Milk, Kietipong Pensiripun

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A Wescor Vapor Pressure Osmometer measured the osmolality of a solution by sensing the vapor pressure above the solution in a closed chamber. The instrument sensing element comprised a precision thermocouple which measured the dew point temperature depression, a function of the water vapor pressure in the chamber. It used approximately 5-7 microliter samples to saturate a 0.64 cm filter paper disc. The instrument fixed a milliosmolal digital reading and signaled test completion in 110 seconds. The instrument weighed approximately 3. 62 kilograms, was 26. 7 x 24. 1 x 10. 2 cms in size and had a range of …

Effect Of Processing On Aliphatic Aldehyde Content Of Turkey Meat, Carolyn G. Ponce

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nitrite at the level found in turkey frankfurter formulations vii did not interfere in the hydrazone test as developed by Andrews (1975). The aldehyde levels of frankfurters made principally from MD turkey meat were, on the average, twice as high as the levels in the raw meat. Aldehyde levels generally increased as the frozen storage time of the raw meat increased. There were some variations from this trend due to variation in the fat content of the raw meat. Sixty days was recommended as a maximum frozen storage time. However, because of variation in the fat content from sample to …

Manufacture Of Cottage Cheese Utilizing A Ph-Controlled, Whey-Based Lactic Culture, Yen-Luon Chen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Eleven strains of lactic cultures were used to determine their effectiveness in different bulk culture media for the manufacture of Cottage cheese. The acid phosphate-treated whey-based medium (APWM) made from Cottage cheese whey was found to be as effective as sweet phosphate-treated whey-based medium (PWM) made from Swiss cheese whey in supporting the development of lactic cultures. The relative activity of cultures in APWM with pH control was higher than phage inhibitory medium and nonfat dry milk without pH control. APWM was used successfully in the manufacture of Cottage cheese. Greater reliability and shorter cutting time resulted, and the product …

Applicability Of An Electronic Semiautomatic Somatic Cell Counter To Dairy Herd Improvement Milk Sample Testing, Nianwei Wang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Technicon OSCC II was evaluated for application in dairy herd improvement central laboratories. Dilution using a Fisher Autodiluter made sample preparation for assay less time consuming and more convenient and resulted in the same accuracy as with the manual syringe technique.

Sample storage and the presence of a potassium dichromate preservative tablet had little effect on somatic cell count when tested within two days at room temperatures (20-23 C) or within four days at refrigeration temperatures (4-7 C). The preservative tablet caused an average increase of 14,000 cells/ml. The average cell count dropped 26 percent following two days at …

Effect Of Zinc Nutriture And Contraceptive Steroid Injection On Body Composition Of Young Female Rats, Sang Ai Hahn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Forty-nine female rats initially weighing about 95 grams were used in this experiment to determine the effect of contraceptive hormones on body composition in zinc deficient and zinc supplemented rats. Four treatment groups were: 2 ppm of dietary zinc with daily contraceptive steroid injections, or with placebo injection, and 140 ppm of dietary zinc with contraceptive steroid injection or with placebo. The daily injected steroids consisted of 0.1ug of Ethynyl Estradiol and 0.1mg of Medroxyprogesterone in 0.1ml of corn oil. Non-hormone treated groups received 0.1ml of plain corn oil. All injections were administered into the Gluteus Maximus muscle. Food intake, …

Mechanical Desinewing Of Meat, Kamchorn Tantikarnjathep

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effects of mechanical desinewing on yield, proximate analyses and connective tissue content of pork and beef have been examined and its influence on the appearance and palatability of cooked salami was evaluated. Mechanical desinewing removed approximately half of the connective tissue and reduced the tendency for formation of gelatin pockets in cooked salami. Yields from the desinewer ranged from 71 to 87 percent, however, cooking yield defined as cooked weight divided by uncooked weight from the desinewed salami were 6 to 7 percent higher than from the nondesinewed salami. For both the beef and pork there was no significant …

Comparison Of Compatibility Of Streptococcus Starters In Reconstituted Nonfat Dry Milk And A Whey-Based Bacteriophage Inhibitory Medium, Clinton K. Searle

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Compatibility of mixed cultures of Streptococcus lactis and Streptococcus cremoris were studied by the phage tracer technique in 10% nonfat dry milk and a whey-based phage inhibitory medium. Methods of membrane dialysis and differential enumeration were tried and abandoned. Dominance occurred in nonfat dry milk and in the whey-based medium during a continuous fermentation period within a pH range 6.8 to 5.2. The dominance pattern of two-strain combinations in 10% nonfat dry milk was different from that in the whey-based media. Dominance varied from one strain to another in no consistent sequence in some combinations. Dominance patterns of combinations were …

A Five-Year Follow-Up Study: Relationship Of The High Pufa Diet Used In Original Study Of Middle-Aged Adults To Present Dietary Choices, Rate Of Erythrocyte Hemolysis And Serum Cholesterol And Triglyceride Values, Jeanette Parsons Egan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was a follow-up of the Christiansen study which was completed in 1967. Dr. Christiansen's 26 subjects ranged in age from 33 to 60 years. Ten were designated as controls and the other 16 were placed on a high polyunsaturated fatty acid (PUFA) diet for a period of 26 weeks.

The purpose of doing a follow-up was to determine what effect the study had on present dietary patterns, serum lipid levels and rate of erythrocyte hemolysis.

Eighteen of the original subjects participated in this study. Of these 18, nine were from the control group and nine were from the …

Evaluation, Assay, Distribution, And Survey Of Staphylococcus Aureus Thermonuclease In Milk And Cheese Products, Gene Leong Hong

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The metachromatic agar-diffusion test of Lachica, Hoeprich, and Genigeorgis (1971) was modified by adding 17 ml of the agar medium to a 100 by 15 mm plastic petri dish, using 5 µl samples and 3 mm wells. The test detected 0.5 ng/ml of thermonuclease in 3 hr at 37 C. This was equivalent to 10⁶ to 10⁷ cells/ml of Staphylococcus aureus strains 196 E, 14458, and 19095 grown in Brain Heart Infusion (BHI) broth. The test sensitivity was decreased ten fold in raw and pasteurized milk.

One-half gram of cheese was dissolved in 4.5 ml of 0.1 M …

Milk Protein Analysis By Automated Ultraviolet Spectroscopy, R. Ford Wilkinson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An automated continuous flow analysis for milk protein utilizing ultraviolet spectroscopy resulted in a correlation coefficient of 0.972 and a standard estimate of error of 0.082 percent protein when 30 samples were compared with the acid orange 12 dye binding method. Milk was solubilized in 95-105 volumes of acetic acid using the Technicon Auto Analyzer II and measured for absorbance at 274 nanometers. No deviation from the standard method due to mastitis and varying milk fat concentration was observed. A theoretical model indicated a possible standard estimate of error 0.059 percent protein due to inter- and intra-breed variation in milk …

The Effects Of Gamma Irradiation, Color Mutation And Various Subatmospheric Pressures On The Growth And Patulin Production By Penicillium Expansum And Penicillium Patulum, Karl B. Adams

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

To assess the effects of gamma radiation at low doses, spores of Penicillium expansum NRRL 971 and Penicillium patulum NRRL 989 were exposed to doses of 0, 50, 100, 150, and 200 krads. The amount of patulin for each culture was quantitatively determined and growth at each dose was evaluated. The results showed a 31% increase in the amount of patulin synthesis after a dose of 150 krads for Penicillium expansum. At 200 krads, both fungi showed low levels of patulin production and inhibited growth.

Eight color mutants of P. expansum and eight color mutants of P. patulum were produced …

Anthocyanins Of Fresh And Stored Freeze-Dried Sour Cherries In Compressed Form, Suwan Potewiratananond

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Anthocyanin pigments of sour cherry (prunus cerasus L., cultivar Montmorency) fruit were studied by spectrophotometry, paper and two-dimensional thin layer chromatography and disc electrophoretic method. Mature and wholesome fresh sour cherries and freeze-dried compressed sour cherries stored at 70 F and 100 F for 6 months were used.

A total of seven anthocyanin pigments were observed in both paper and thin layer chromatograms of the fresh and freeze-dried compressed samples stored for O month whereas the freeze-dried compressed samples stored at 70 F and 100 F for 6 months showed the retention of three to six pigments. All of …

Manufacture Of Monterey Cheese From Preacidified Milk, Faisal O. Mohamed

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Whole milk acidified to pH 5.3 with hydrochloric acid was used for the manufacture of Monterey cheese. The milk was inoculated with one and one-half percent lactic starter and set with 12.5 ml rennet per 1000 pounds of milk. Normal washing treatments resulted in cheese with moisture in excess of 44 percent. Moisture content was brought below 44 percent by using wash water at a temperature such that the water-curd-whey mixture was 35 C. The pH of cheese made by preacidification was all between 5.21 and 5.09. No acid defects were encountered. Preacidification eliminated chance of spoilage or losses caused …

Effect Of Added Calcium Ions On Relative Milk-Clotting Activities Of Commercial Milk Clotting Enzymes, Nuchanart Pavenayotin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Effect of added calcium ions on the relative milk clotting activities of porcine pepsin, Mucor miehei protease, Endothia parasitica protease, and Mucor pusillus protease was compared with that of rennin. Skimmilk, maintained at pH 6. 3 with 0.000% to 0.030% added calcium chloride, was used as a substrate. The coagulation activity of Mucor pusillus protease appeared to be most sensitive to calcium ions, followed by Mucor rniehei protease, porcine pepsin, rennin, and Endothia parasitica protease. The clotting activities of Mucor pusillus protease were also more sensitive than rennin to added calcium ions in milk samples maintained at pH values of …

Extractable-Emulsifying Capacity Of Hand And Mechanically Deboned Mutton And Organoleptic Acceptability Of Various Mutton Salami Formulations, Jack Robert Anderson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Salt soluble extracts from mechanically deboned mutton were significantly higher (P < .01) in pH than the extracts from the hand boned mutton. An associated trend toward greater extractability, however, was not significant. Variation in emulsifying capacity between extracts from carcass parts were highly significant yet significant variation did not occur in the emulsifying capacity of hand versus mechanically deboned mutton. A new term, extractable- emulsifying capacity is presented which incorporates the extractability and emulsifying capacity of meat extracts into one value which should more accurately estimate the contribution of a meat ingredient in forming a stable sausage emulsion.

Salami, utilizing mutton, was formulated from experimental results which indicated that up to 10 percent mutton fat and 68 percent mutton lean was acceptable to panelists. Pork was preferred to beef for use in combination with mutton as determined by panel scores, however disagreement was noted between panelists. Panelists were unable to detect flavor, moisture or texture differences between the final mutton salami and a commercial beef and pork formulation. They did however prefer the appearance of the mutton salami (P < .05).

Formation And Anatomical Distribution Of Chlorophyll And Glycoalkaloids In Potato (Solanum Tuberosum L.) Tubers And Their Control By Physical And Chemical Treatments, Robert Bruce Jeppsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Applications of growth regulators and modifications of light exposures were investigated regarding their abilities to curtail the normal development of chlorophyll and glycoalkaloids in potato tubers responding to light. Four growth regulators were sprayed on the foliage of potato plants 14 days prior to harvest, of which two (Ethephon and N⁶-Benzyladenine [N6BA]) successfully retarded chlorophyll and glycoalkaloids in the harvested tubers. When tubers were dipped in N6BA, lower concentrations of the chemical promoted glycoalkaloid formation, while larger amounts were more inhibitory. When fluorescent lights were directed through colored cellophane filters, tubers receiving yellow and orange illuminations were inhibited …

Formation And Control Of Chlorophyll, Solanine Alkaloids, And Sprouts Of Potato (Solanum Tuberosum L.) Tubers And Carbonyl Compound Of Tomato (Lycopersicon Esculentum Mill.) Fruits, S. J. Jadhav

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Part I. Formation and control of chlorophyll, solanine alkaloids, and sprouts of potato (Solanum tuberosum L.) tubers

Incorporation of radioactive carbon from acetic acid-2-¹⁴C (sodium salt), β-hydroxy-β-methylglutaric acid (HMG)-3-¹⁴C, L-leucine-U-¹⁴C, L-alanine-U-¹⁴C, and D-glucose-U-¹⁴C into the predominant glycosidic steroidal alkaloids, ⍺-solanine and ⍺-chaconine of potato sprouts was 4.88, 9.0, 15, 24, and 20 times less than that of mevalonic acid (MVA)=2-¹⁴C (DBED salt), respectively. The efficiency ratio revealed that β-hydroxy-β-methylglutaric acid (HMG)-3-¹⁴C was incorporated via acetate or acetoacetate. The distribution of radioactivity originated from D-glucose-U-^{14 …}

Some Factors Affecting The Body And Texture Of Direct Acid Cottage Cheese, Chandarrao G. Kale

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Four lots of Cottage cheese were made from the same pasteurized skimmilk; three lots by a direct acid procedure, and a fourth control lot by a conventional culture method. Direct acid curd was formed by cooling the skimmilk to 4C, acidifying to pH 4.6 with concentrated HCl, and warming by electrical resistance to 32C without agitation. Prior to acidification, the three direct-acid lots were treated as follows: 1- No culture, 2- 5% lactic culture added and the pH allowed to reach 6.0, 3- Same as 2 except the pH was allowed to reach 5.5. The control lot was set at …

The Effect Of Heat Treatment Of Fresh Frozen Vells On Rennin Extractability, Leesther Mifflin Holm

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A procedure was developed for the extraction of rennet from fresh frozen vells. Frozen vells were minced in a Model VCM-25 Hobart Vertical Cutter/Mixer. Dry sodium chloride was added until the salt concentration in the moisture of the tissue was 10%. Salted tissue was placed in galvanized steel cells and heated in a water bath to 49, 54, 57 and 60 C for 0, 15, 30, 45 and 60 minutes. The heated tissue was dried to about 4% moisture at ambient temperature with the aid of an electric fan. The dried salted tissue was extracted with a sodium chloride solution …

Effects Of Water Quality On Physico-Chemical And Organoleptic Characteristics Of Selected Canned Fruits And Vegetables, Anita Kay Wilson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effect of processing water quality, specifically calcium and magnesium salt content (0-500 mg/1) and the addition of chelating agents (0-250 mg/1 of aminopolycarboxylic acids, polyphosphates, hydroxycarboxylic acids or phytates), upon physico-chemical and organoleptic characteristics of canned Jonathan and Delicious apple slices, Montmorency cherries and Blue Lake green beans was investigated.

Physical determinations: shear values, turbidity of syrup or brine measured via light transmittance, Hunter color and color difference meter readings and internal can corrosion; chemical composition: pectin as calcium pectate, volatile reducing substances, total acidity, pigment determinations, nitrate-nitrogen values; and sensory measurements: texture, shape, flavor, aroma, color value and …

Effects Of Zinc Deficiency On Hemoglobin, Red Cell Counts, Red Cell Fragility And Circulating And Storage Levels Of Zinc, Iron And Copper In The Rat, Rekha R. Dalvi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Three experiments were conducted to study the effect of zinc deficiency on hemoglobin, red cell counts, red cell fragility, storage of erythropoietic minerals in livers and circulating levels of zinc, iron and copper in the rat.

In the experiment 1, twenty weanling rats were divided into four groups. Two groups were fed zinc-deficient diet ( <0.5 ppm); and two groups, zinc-supplemented diet (50 ppm). The rats in the first and third groups were bled three times a week (bled), however the rats in remaining groups were bled once a week (non-bled). All rats received ad libitum food.

Mean food intake per day was considerably less for zinc-deficient rats than that for zinc-supplemented rats. Approximately 2 to 3 times as much food was required for each gram of body weight gained by the zinc-deficient group as by the controls.

In the experiment 2, …

The Effects And Desirability Of Utilizing Dried Whey In Selected Food Products, Katherine P. Robinson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effects and desirability of utilizing dried whey in pie crust, muffins, and beef gravies were studied using taste panel evaluations and objective testings.

In pastry the addition of whey caused significant changes. As the whey level increased to 10 percent of the flour weight, the crust became browner during baking and the shortometer recorded an increase in tenderness. The taste panel noted as whey levels increased to 10 percent and above that the color became yellow instead of creamy white; the flavor became undesirable; and pastry became less tender and flaky.

Whey significantly increased the desirability of muffins by …

A Procedure For Measuring Residual Rennin Activity In Whey And Curd From Freshly Coagulated Milk, Jorge Reyes

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A procedure was developed for measuring residual rennin activity in curd extracts and whey. A sensitive substrate at pH 5.8 was prepared by mixing 6 grams of low-heat nonfat dry milk in 500 milliliters buffer containing 0.05 molar cacodylic acid, 0.02 molar calcium chloride, and 0.012 molar triethanolamine, and storing it at 2 degrees centigrade for 18 hours. Two milliliters of whey or curd extract were inoculated into 25 milliliters of substrate at 30 degrees centigrade. The coagulation time was measured and compared to that induced by 2 milliliters of a known rennin concentration added at the same time to …

Selected Physio-Chemical, Microbiological, And Agronomical Studies On The Controlled Atmosphere Storage Of Sugarbeet (Beta Vulgaris) Roots, Vinod V. Karnik

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The post-harvest physiology of sugarbeet (Beta vulgaris) roots was studied during controlled atmosphere (CA) storage at 35° and 50°F. Zero, 3, 6 and 10% carbon dioxide and 5% oxygen concentrations were employed to investigate the most beneficial concentrations of gases. Under the experimental conditions beets were stored successfully for 200 days. The maximum beneficial effects of CA were observed under 6% carbon dioxide and 5% oxygen at 35°F. Regardless of storage temperatures, sucrose retention was highest in the beets stored under CA, compared to conventional refrigeration (CR). Other beneficial effects include less hydrolysis of sucrose to reducing sugars …

Development Of A Whey-Based Lactic Culture Medium Capable Of Bacteriophage Inhibition, Chao Tung Cheng

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A whey product has been formulated for use as a lactic starter medium. Phosphate-treated whey medium (PWM) has been shown to support growth of lactic cultures and prevent phage proliferation. Comparisons were made of a commercial phage inhibitory medium (PIM), reconstituted non-fat dry milk (NDM) and PWM. PWM inhibited all phages tested and stimulated starter growth. PWM was not as stimulating as PIM but was better than NDM. Good Cheddar cheese has been made using PWM. PWM is more economical than PIM but NDM is the most economical one if cheese yield is considered.

Raffinose In The Sugarbeet (Beta Vulgaris): I. Biosynthesis And Degradation In The Root; Ii. Hydrolysis In Molasses With Sweet Almond Emulsin, Te-Chao Chuang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

PART I

The precursors for the biosynthesis of raffinose in sugarbeets were studied.

An enzyme preparation was obtained from the sugarbeet (Beta vulgaris) root. Incubation of this enzyme with (X-galactose-1-phosphate, Uridine triphosphate (UTP), Adenosine triphosphate (ATP), Magnesium chloride (MgCl₂), and L- cysteine at pH 5, 10°c for 6 hours formed a compound which was identified as raffinose by a hydrolysis method and thin- layer chromatography. The same result was obtained when Uridinediphosphate (UDP)-galactose was incubated with sucrose, ATP , MgCl₂, and L- cysteine in the presence of the beet enzyme preparation. These reactions suggested …