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Levels Of Acetic And Lactic Acid In Rte Meat And Poultry Products And Their Association With Occurrence Of Listeria Monocytogenes At Retail, Omaima Maamoun Ahmed
Levels Of Acetic And Lactic Acid In Rte Meat And Poultry Products And Their Association With Occurrence Of Listeria Monocytogenes At Retail, Omaima Maamoun Ahmed
Doctoral Dissertations
The purposes of this study were (1) to quantify the levels of acetic, and lactic acid occurring in approximately 1800 retail ready-to-eat (RTE) processed deli meat and poultry products to determine the impact of current antimicrobial lethality treatments on occurrence of Listeria monocytogenes (LM) at retail, (2) to determine if the intrinsic levels of lactic acid (LA) produced by lactic acid bacteria (LAB) of the processed RTE meat or poultry affect the extrinsic levels of lactic acid added in RTE meat and poultry products, and (3) to evaluate 2%LA for its effect as a post-lethality treatment on the survival of …
Use Of High Pressure Homogenization In Bacterial Inactivation, Panchalee Pathanibul
Use Of High Pressure Homogenization In Bacterial Inactivation, Panchalee Pathanibul
Masters Theses
High pressure homogenization has been of growing interest as a nonthermal technology for the inactivation of microorganisms in fruit and vegetable juices. Cells of Escherichia coli and Listeria innocua, used as surrogates for foodborne pathogens, were inoculated into apple or carrot juice (~7 log₁₀ CFU/ml) containing 0 or 10 IU/ml nisin and subjected to 350 to 0 MPa high pressure homogenization. At 50 MPa homogenization pressure intervals, juice samples were collected, immediately cooled to <10°C, and then serially diluted and plated on nonselective recovery media. Following incubation, survivors were enumerated. As processing pressure increased, inactivation of E. coli increased, and a >5 log reduction of cells was achieved following exposure to pressures in excess >250 MPa. In contrast, little inactivation was observed for L. innocua with pressure <250 MPa and up to 350 MPa processing pressure was required to achieve an equivalent 5 log inactivation. The addition of 10 IU nisin, together with high pressure homogenization, did not exhibit significant additional E. coli inactivation, but interactions were observed with L. innocua. Results indicate that high pressure homogenization processing is a promising technology to achieve pathogen decontamination in fruit and vegetable juices.
Rapid Molecular Detection Of Salmonella From Produce Using Real-Time Pcr, Nathan D. Miller
Rapid Molecular Detection Of Salmonella From Produce Using Real-Time Pcr, Nathan D. Miller
Masters Theses
Recent outbreaks of Salmonella linked to fresh produce emphasize the need for rapid and sensitive assays to help control outbreaks. Reverse-transcriptase PCR (RT-PCR) detects the presence of mRNA (shorter half-life than DNA), with greater potential of detecting viable cells. Rapid real-time methods using fluorescent dyes and probes simultaneously detect and confirm the presence of target nucleic acid, eliminating the need for gel electrophoresis. The objective of this research was to rapidly detect Salmonella Typhimurium from spiked lettuce, tomatoes, and peppers using real-time RT-PCR. Washed and ultraviolet light treated lettuce (~25gram), tomato (~100g), and peppers (~130g) samples were inoculated with high …
Effects Of Lipids, Amino Acids, And Beta-Cyclodextrin On Gelatinization, Pasting, And Retrogradation Properties Of Rice Starch., Xiaoming Liang
Effects Of Lipids, Amino Acids, And Beta-Cyclodextrin On Gelatinization, Pasting, And Retrogradation Properties Of Rice Starch., Xiaoming Liang
LSU Historical Dissertations and Theses
The primary purpose of this study was to determine the addition of lipids, amino acids, and beta-cyclodextrin effects on commercial rice starch gelatinization, pasting, and retrogradation properties by using differential scanning calorimetry (DSC), rapid visco analysis (RVA), and x-ray diffractometry (XRD). Analyses from commercial rice starch showed that the presence of 0.6% monopalmitin (MP) increased the peak viscosity (PV), minimum viscosity (MV), and final viscosity (FV) by 38, 27, and 72 RVU respectively. The pasting temperature was also increased by 6°C, whereas the total setback (TSB) was increased by 45 RVU. Incorporation of lysophosphatidylcholine (LC) and lysophosphatidylethanolamine (LE) also showed …
The Effect Of Storage On Consumer Preference, Sugar Content, And Starch Content Of Spiced Low-Fat Sweet Potato Flavored Yogurt., Mohammad Abdulrahman Al-Fayez
The Effect Of Storage On Consumer Preference, Sugar Content, And Starch Content Of Spiced Low-Fat Sweet Potato Flavored Yogurt., Mohammad Abdulrahman Al-Fayez
LSU Historical Dissertations and Theses
The primary purpose of this study was to determine if addition of pumpkin pie spice to sweet potato puree would enhance consumer acceptance of sweet potato flavored yogurt. In Phase I, the effect of fat percentage, spice percentage, and addition of sweet potato pre-fermentation and post-fermentation on consumer acceptance was examined to determine the optimum treatment preferred by consumers and the effect of each treatment variable on the fermentation process. Phase II focused on the effect of storage periods of 7, 14, and 21 days on the organoleptic qualities and chemical composition of sweet potato. Analyses showed that the percentage …
Studies On Shrink -Wrapping And Low-Oxygen Storage Of 'Beauregard' Sweet Potatoes (Ipomoea Batatas (L.) Lam.)., Anthony Wathome Kilili
Studies On Shrink -Wrapping And Low-Oxygen Storage Of 'Beauregard' Sweet Potatoes (Ipomoea Batatas (L.) Lam.)., Anthony Wathome Kilili
LSU Historical Dissertations and Theses
The applicability of using shrink-wrap films in sweetpotato storage was investigated. 'Beauregard' sweetpotatoes were individually wrapped in either Cryovac D955, Clysar EHC50, Clysar EHC60 or Clysar EHC75 shrink-wrap film and a nonwrapped control. Roots were also overwrapped in 2.3-kg packages using Cryovac D955 or Clysar EHC75 films. Wrapped and nonwrapped roots were stored at either 7°C, 15.6°C or 22°C for five weeks followed by one week at 22°C. Shrink-wrapped roots exhibited increased sprouting. Roots wrapped in EHC75 film had less weight loss and increased sucrose compared to the other films. Shrink-wrapped roots were higher in sucrose content but were not …
Reduction Of Endogenous Bacteria Associated With Catfish (Ictalurus Punctatus) Fillets Using The Grovac Process., Milton Ruben Ramos
Reduction Of Endogenous Bacteria Associated With Catfish (Ictalurus Punctatus) Fillets Using The Grovac Process., Milton Ruben Ramos
LSU Historical Dissertations and Theses
Fresh catfish (Ictalurus punctatus) fillets (CF) can serve as vehicles for spoilage and pathogenic bacteria. Concern for the microbiological safety of chilled CF has grown lately because psychrotrophic pathogens can survive and grow at refrigeration temperatures. The Grovac method, a new, patented (U.S. 5,543,163) process is being used in an attempt to reduce the growth of pathogens and spoilage microorganisms in CF. This process involves the using of a process solution of ascorbic acid (AA) and sodium chloride (NaCl), vacuum and tumbling. Specific objectives of this study included the isolation and identification of endogenous microflora associated with fresh whole catfish …
Production Of L-(+) Lactic Acid From Blackstrap Molasses By Lactobacillus Casei Subspecies Rhamnosus Atcc 11443., Narumol Thongwai
Production Of L-(+) Lactic Acid From Blackstrap Molasses By Lactobacillus Casei Subspecies Rhamnosus Atcc 11443., Narumol Thongwai
LSU Historical Dissertations and Theses
Lactobacillus casei subspecies rhamnosus grew on non-supplemented blackstrap molasses. The bacteria grew best at the optimal temperature of 40 +/- 2°C, and at pH 5.5. Addition of yeast extract to molasses shortened the lag phase and increased cell mass. In batch fermentations without pH control, the highest ratio of lactic acid produced to cell mass was 12 from non-supplemented molasses. For pH controlled batch fermentations, the ratio's of lactic acid produced/cell mass were 81, 79, 51 and 31 for 0, 0.2, 0.4 and 0.8% yeast extract supplementation, respectively. Non-supplemented molasses, 8% Brix, produced 28 +/- 2 g/l of lactic acid …
The Potential Of High Oryzanol Rice Bran Oil As An Antioxidant In Whole Milk Powder., Jackin Njagi Nanua
The Potential Of High Oryzanol Rice Bran Oil As An Antioxidant In Whole Milk Powder., Jackin Njagi Nanua
LSU Historical Dissertations and Theses
Lipid autoxidation of whole milk powder (WMP) during storage lowers its organoleptic quality and causes accumulation of oxidation products. This study evaluated the effectiveness of high-oryzanol (2.5%) rice bran oil (RBO) as an antioxidant in WMP. The powder was fortified with 0.1% and 0.2% RBO and its oxidation studied during accelerated storage at 45°C and 0.31 water activity for 40 days. Free radicals were determined by electron spin resonance spectroscopy. Oxidation was estimated by determining thiobarbituric acid reactive substances (TBARS) and cholesterol oxidation products using gas chromatography. The effect of RBO on flavor and consumer preference of freshly manufactured milk …
Prevention Of Hydrolytic And Oxidative Rancidity And Nutrient Losses In Rice Bran During Storage., Fatemeh Malekian Ramezanzadeh
Prevention Of Hydrolytic And Oxidative Rancidity And Nutrient Losses In Rice Bran During Storage., Fatemeh Malekian Ramezanzadeh
LSU Historical Dissertations and Theses
Freshly milled raw rice bran was stabilized with microwave heat for 3 min. Half of raw and treated bran were packed in Ziplock(c) bags and the other half vacuum packed. Half of the samples were stored at 4--5°C and the other half at 25°C for 16 weeks. The free fatty acid (FFA) content increased rapidly in raw rice bran samples vacuum packed and samples packed in Ziplock(c) bags store at 25°C from an initial amount of 2.5% to 54.3% and 48.1%, respectively. FFA level increased significantly in raw samples vacuum packed and packed in Ziplock (c) bags stored 4--5°C from …
Rapid Assessment Of The Bacteriological Quality Of Milk By The Use Of Adenosine Triphosphate Bioluminescence., Pushpa John Samkutty
Rapid Assessment Of The Bacteriological Quality Of Milk By The Use Of Adenosine Triphosphate Bioluminescence., Pushpa John Samkutty
LSU Historical Dissertations and Theses
Raw milk samples (n = 246) and pasteurized milk samples (n = 104) were analyzed to determine adenosine triphosphate (ATP) and compared with the standard plate count (SPC). An ATP filtration method was used to filter milk samples prior to ATP determination, which was measured in relative light units (RLU). The ATP assay took approximately 7 minutes to complete and could allow rapid prediction of SPC which is a measure of raw milk quality. Linear regression analysis was performed on data from three raw milk treatments defined as; fresh milk samples, samples preliminarily incubated at 12.8 and 15.6$\sp\circ$C for 18 …
Granular Activated Carbon From Agricultural By-Products: Carbon Properties And Their Relationship To Sugar Decolorization Potential., Mohamed Ahmedna
Granular Activated Carbon From Agricultural By-Products: Carbon Properties And Their Relationship To Sugar Decolorization Potential., Mohamed Ahmedna
LSU Historical Dissertations and Theses
Representative samples of soft, low density, group 1 (rice straw, rice hulls, sugarcane bagasse) and hard, high density, group 2 agricultural by-products (pecan shells) were converted into granular activated carbons (GACs). Prior to pyrolysis, group 1 by-products were mixed with four binders, sugarcane molasses, sugar beet molasses, corn syrup and coal tar. GACs were produced from group 1 and 2 materials by physical activation (carbon dioxide, steam) or from group 2 materials by chemical activation (phosphoric acid). Carbons were evaluated for their physical (hardness, bulk density), chemical (ash, pH), surface (total surface area, pore size distribution, surface oxides) and adsorption …
The Effects Of Homogenized Cream And Commercial Buttermilk Powder On Low-Fat Cheddar Cheese., Tonya Conner Schoenfuss
The Effects Of Homogenized Cream And Commercial Buttermilk Powder On Low-Fat Cheddar Cheese., Tonya Conner Schoenfuss
LSU Historical Dissertations and Theses
Seventy percent reduced fat Cheddar cheese was manufactured with homogenized cream and sweet cream buttermilk powder in an effort to improve flavor and texture characteristics. Manufacturing procedures, as well as the chemical, physical and sensory attributes. Pasteurized cream was homogenized (15.8 MPa) with and without the addition of buttermilk powder. The cream was added to pasteurized skim milk to produce two vats of cheese, one with and one without buttermilk powder. After milling, each vat was split to produce a washed curd and normal curd cheese. The four cheeses were sampled at week one, and months one, two and four. …
Acid Solubilization Of Fish Protein For Production Of Protein Hydrolysate., Ercument Ozer
Acid Solubilization Of Fish Protein For Production Of Protein Hydrolysate., Ercument Ozer
LSU Historical Dissertations and Theses
The mechanism of fish protein solubilization by acid hydrolysis at elevated temperatures was investigated. Rate expressions for the solubilization were determined using pilot scale data with two different rate determination methods. A postulated mechanism was verified and estimated rates were evaluated on five independent verification experiments. A functional relationship between nonprotein byproduct concentration and whiteness of fish protein hydrolysate (FPH) was developed. Initial and set-point operating variables were calculated to produce FPH with acceptable color characteristics for food use. A batch reactor was used for duplicate hydrolysis trials conducted at three acid and three temperature levels for four hours. Samples …
Thiamine, Riboflavin, And Sensory Stability Of Irradiated Brown Rice., Linda Chamberlain Douglas
Thiamine, Riboflavin, And Sensory Stability Of Irradiated Brown Rice., Linda Chamberlain Douglas
LSU Historical Dissertations and Theses
While brown rice is nutritionally superior to white rice, it is not shelf stable, becoming rancid in a matter of weeks. Preservation by refrigeration or freezing is expensive and not universally available. Therefore, other preservation methods, such as aqueous ethanol extraction of lipids, have been studied to overcome this problem, but these methods also have limitations. The effects of gamma-irradiation on the physicochemical properties and lipase activity in brown rice has been well documented. Gamma-irradiation has been shown to reduce lipase activity, presumably preserving sensory quality. A sensory study of 2 Louisiana grown varieties (Mars and Lemont) of irradiated brown …
Aqueous Processing Influences On Composition And Functionality Of Mechanically Separated Broiler Meat., Henri Khalil Salman
Aqueous Processing Influences On Composition And Functionality Of Mechanically Separated Broiler Meat., Henri Khalil Salman
LSU Historical Dissertations and Theses
The demand for breast meat has caused a surplus of broiler legquarters, which cannot be easily or efficiently deboned by hand. Oxidative stability and texture of mince recovered with two mechanical deboners, a belt/drum separator with 5 mm (BD5), 2 mm (BD2), and 5 mm followed by 2 mm (BD5/2) drum or auger/sieve (SD) deboner with slit openings of 0.25 mm, were evaluated. Mechanical deboned chicken meat (MDCM) had higher fat, ash and lower moisture than hand deboned meat. BD2 meat contained calcium at levels below those allowed by USDA, but had higher fat that decreased oxidative stability. Washing of …
Development Of An Optimal Systems Criteria In The Performance Evaluation Of A Crawfish Sorting Machine., Rommel Gaac Tangonan
Development Of An Optimal Systems Criteria In The Performance Evaluation Of A Crawfish Sorting Machine., Rommel Gaac Tangonan
LSU Historical Dissertations and Theses
This study aimed to: (1) establish a set of optimally configured guidelines for performance testing of crawfish sorting machines; (2) examine biophysical characteristics of crawfish and machine-related design parameters; and, (3) write computer programs covering the essential aspects of the crawfish sorting process. Three crawfish sorting machines were tested in the Spring of 1994 and 1995: (1) cylindrical roller sorter machine, (2) diverging vane belt sorter machine, and (3) grid shaker sorter machine. Both the cylindrical roller sorter and the diverging vane belt sorter separated crawfish into four groups: peeler, medium, large and jumbo; the grid shaker sorter, however, separated …
Changes Of Antioxidants And Fatty Acid Composition In Stabilized Rice Bran During Storage., Taisun Shin
Changes Of Antioxidants And Fatty Acid Composition In Stabilized Rice Bran During Storage., Taisun Shin
LSU Historical Dissertations and Theses
The effects of extrusion temperature and post extrusion holding time, microwave heating, and gamma irradiation on antioxidants and lipid composition in rice bran were studied. Post extrusion holding time had no apparent effect on rice bran stability. Increased holding times reduced (p $<$ 0.05) total vitamin E. Oryzanol concentration was lower (p $<$ 0.05) only with 6 min holding time. Inactivation of lipolytic enzymes was obtained by extrusion temperatures of 120, 130, and 140$\sp\circ$C. Increased extrusion temperatures reduced the retention of vitamin E and oryzanol during storage. An extrusion temperature of 110$\sp\circ$C provided the highest retention of vitamin E and oryzanol during storage although FFA level was higher (p $<$ 0.05) than that of the other extrusion temperatures from 105 to 375 days. There were no significant (p $>$ 0.05) decreases in individual vitamin E vitamers until 4 min microwave heating. After 8 min heating, individual E vitamers decreased significantly (p $$ 0.05) in FFA level by 24 weeks of storage with microwave heating for 12 min. Microwave heating for 4, 8, and 12 min did not provided adequate inactivation of lipolytic enzymes. Total vitamin …
Enzymatic Hydrolysis Of Crawfish Processing By-Products For Bioflavor Production., Hyung-Hee Baek
Enzymatic Hydrolysis Of Crawfish Processing By-Products For Bioflavor Production., Hyung-Hee Baek
LSU Historical Dissertations and Theses
Crawfish processing by-products (CPBs) were hydrolyzed using protease to evaluate the potential for bioflavor production. Ten commercial proteases (neutral and alkaline) were tested at both 37$\sp\circ$C and their optimum temperatures using CPBs as substrate. Of these, APL-440 was selected for enzymatic hydrolysis of CPBs on the basis of activity per cost. Response surface methodology (RSM) was used to optimize the hydrolysis of CPBs using APL-440. Optimum hydrolysis conditions for enzymatic hydrolysis of CPBs with APL-440 were determined to be pH 8-9, 65$\sp\circ$C, 2.5 hr reaction time, 75% substrate concentration, and 0.3% APL-440. Two types of CPBs (composite and claw) were …
Instrumental And Sensory Characterization Of The Flavor Of Blue Crab (Callinectes Sapidus) Meat And Processing By-Product., Hau Yin Chung
Instrumental And Sensory Characterization Of The Flavor Of Blue Crab (Callinectes Sapidus) Meat And Processing By-Product., Hau Yin Chung
LSU Historical Dissertations and Theses
Blue crab (Callinectes sapidus) meat and its processing by-product (CPB) were characterized by instrumental, olfactometric, and sensory techniques to determine the usefulness of CPB as a feed stock for flavor recovery. Instrumental analysis with gas chromatography/mass spectrometry (GC/MS) and gas chromatography/Fourier transformed infrared spectroscopy (GC/FTIR) allowed for the identification of 77 and 80 compounds in claw meat and CPB, respectively. Fifty-five compounds were found common to both samples, suggesting that CPB could be a good source for flavor recovery. Quantitatively, trimethylamine (TMA), alkanes (C15-C17, C19), and indole were high ($>$50ng/g) in claw meat while TMA, carbon disulfide, dimethyltrisulfide, alkanes …
Sulfadimethoxine Analysis In Channel Catfish: A Model Drug Residue Monitoring Program For Aquaculture., Calvin Charles Walker
Sulfadimethoxine Analysis In Channel Catfish: A Model Drug Residue Monitoring Program For Aquaculture., Calvin Charles Walker
LSU Historical Dissertations and Theses
Analytical methods for extraction, detection, and quantitation of sulfadimethoxine (SDM) residues in channel catfish muscle and plasma were developed for a tiered residue monitoring program. The plasma and muscle concentrations of SDM and its primary metabolite in channel catfish, 4-N-acetylsulfadimethoxine (N-acetyl SDM), were determined in SDM medicated fish. Drug extraction methods using matrix solid phase dispersion (MSPD), drug screening methods using enzyme-linked immunoassay (ELISA), and drug residue quantitation methods using high pressure liquid chromatography (LC) are presented. All methods were developed for the simultaneous extraction and analysis of the parent compound and metabolite. MSPD extracts of muscle or plasma were …
Recovery Of Sugars From Cane Molasses By Continuous Simulated Moving Bed Ion-Exclusion Chromatography., Khalid Iqbal
Recovery Of Sugars From Cane Molasses By Continuous Simulated Moving Bed Ion-Exclusion Chromatography., Khalid Iqbal
LSU Historical Dissertations and Theses
Present investigation was undertaken to determine the feasibility of using a Simulated Moving Bed (SMB) Ion Exclusion Chromatographic system for the recovery of sugars from molasses. The recovery of sugars from molasses is complicated because of the presence of high concentration of salts of K, Ca, Mg, etc. The presence of these salts in the molasses prevents sucrose to crystallize. SMB Ion Exclusion Chromatography has been shown to be successful to recover sugars from beet molasses, and to separate sugars from each other in High Fructose Corn Syrup industry. The basis of the ion exclusion is that the sorbent used …
Influence Of Storage Temperature And Duration On Deterioration Of Film-Wrapped And Non-Wrapped Mustard, Brassica Juncea Coss., Regina Poillion Bracy
Influence Of Storage Temperature And Duration On Deterioration Of Film-Wrapped And Non-Wrapped Mustard, Brassica Juncea Coss., Regina Poillion Bracy
LSU Historical Dissertations and Theses
Mustard "greens' is a popular fresh vegetable, especially in the South. Fresh market production, however, is restricted to local sales or short-distance markets due to the relatively short shelf life of mustard. Packaging has been shown to successfully extend the shelf life of several fruits and vegetables. To determine the effect of packaging and storage temperature on the postharvest life and quality of mustard, mustard was stored at 1, 4, and 15C in perforated polyethylene bags, Cryovac D-955 60-gauge or 100-guage heat-shrinkable films or not-wrapped. A preliminary experiment was conducted with spinach to develop experiment methodology and for comparison of …
Functionality And Binding Of Washed Mechanically Separated Beef In Restructured Meats., Kyung Chul Koh
Functionality And Binding Of Washed Mechanically Separated Beef In Restructured Meats., Kyung Chul Koh
LSU Historical Dissertations and Theses
Binding and texture are important attributes of restructured meats which are dependent upon protein properties. Meat was pre-salted with 0, 2.25, 4.5, 6.75, or 9.0% sodium chloride (NaCl) and extracted with buffers (pH 6.0) containing 0, 0.6, 1.2, 1.8, or 2.4 M NaCl to determine total extractable protein (TEP). Increased NaCl level in extraction buffers increased TEP, but NaCl levels of 2.25 and 4.5% in meat interfered with release of solubilized proteins into extraction solutions. Restructured beef roasts of 0, 0.45 or 0.9% NaCl and 0, 0.225 or 0.45% sodium tripolyphosphate (STPP) were manufactured with 10% mechanically separated beef (MSB), …
Rice Bran Stabilization By Improved Internal And External Heating Methods., Jiaxun Tao
Rice Bran Stabilization By Improved Internal And External Heating Methods., Jiaxun Tao
LSU Historical Dissertations and Theses
Rice bran stabilization was conducted by internal (microwave), external (oven drying and steam retorting) heating and non-heating ($\sp{60}$Co irradiation) treatments to improve currently used methods. Two commercial rice varieties cultivated in Louisiana, one long grain (Lemont) and a medium grain (Nato), were milled to collect bran samples. The bran was analyzed for its proximate composition and various physical and thermal characteristics. The proximate composition for long and medium grain bran, respectively, was: moisture, 11.2% and 10.8%; protein, 16.07% and 16.20%; fat, 19.20% and 21.97%; crude fiber, 8.49% and 8.41%; ash, 9.23% and 9.46%; and nitrogen-free extract, 47.01% and 44.07%. Physical …
Comparison Of Clinical Isolates Of Klebsiella Pneumoniae To Klebsiella Sp. Isolated From Summer Harvested Eastern Oysters, Crassostrea Virginica (Gmelin)., Thomas Elbert Graham
Comparison Of Clinical Isolates Of Klebsiella Pneumoniae To Klebsiella Sp. Isolated From Summer Harvested Eastern Oysters, Crassostrea Virginica (Gmelin)., Thomas Elbert Graham
LSU Historical Dissertations and Theses
Suspected environmental fecal coliform positive Klebsiella sp. oyster isolates were analyzed and compared to human clinical isolates of Klebsiella pneumoniae. Oyster isolates were urease negative (at 24 hours) and were identified as K. pneumoniae using API 20E biochemical test strips. The ability to produce fecal coliform reactions was lost by 65% of the oyster isolates after undergoing several passages on brain-heart-infusion agar at 20$\sp\circ$ to 25$\sp\circ$C. Tests with 4-methylumbelliferyl-B-d-glucuronide (MUG) found both oyster and clinical isolates to be MUG negative. Moles % guanine plus cytosine (mol% G + C) information indicated that oyster isolates had mol% G + C values …
Changes In Lipid Composition Of Gulf Coast Marine Species As Influenced By Processing And Storage Treatments., Rafida Idris
Changes In Lipid Composition Of Gulf Coast Marine Species As Influenced By Processing And Storage Treatments., Rafida Idris
LSU Historical Dissertations and Theses
The lipid composition, and changes to lipid components of several marine finfish due to frozen storage, canning and use of various physical and chemical treatments during storage were evaluated. In Phase I, and lipid content of mullet (Mugil cephalus), croaker (Micropogon undulatus), redfish (Sciaenops ocllata) and red snapper (Lutiganus campechanus) fillets obtained from a local supermarket, was approximately 5% with phospholipids representing $<$5% of the total lipid. Vitamin A was not detectable but vitamin E was found in mullet. Mullet had a higher degree of oxidation compared to other species. In Phase II, fresh mullet were wrapped in oxygen impermeable freezer paper or vacuum packaged and frozen at $-$20$\sp\circ$C, or were thermally processed. After 90 days of frozen storage, a second batch of mullet was thermally processed. Total lipid, phospholipid, vitamins A and E and oxidation were determined at 0, 90, 180 and 360 days of storage. TBA number increased by 9.42mg/1000 g after 360 days of frozen storage. Oxidation did not occur in canned fish. Fish canned at 90 days evidenced greater oxidation after canning but further oxidation during storage did not occur. Vacuum packaging inhibited oxidation to a significant degree. Phospholipid decreased in frozen fish to the greatest degree, followed by vacuum packaged samples. Loss of phospholipid in freshly canned mullet was small. In frozen canned mullet, the change was greater. Vitamin E level decreased during frozen storage from 0.69 mg/100 g to a trace amount and the loss was 38% as a result of canning. In Phase III a comparative effect of prefreezing dip treatment, use of antioxidants in the dip and oxygen limitation by vacuum packaging on the lipid composition of frozen stored blackdrum (Pogonius cromis) was studied. Analyses were made at 2 week interval during a 12 week storage period. Total lipid averaged 4% in all treatment samples and phospholipid was $<$5% of total lipids. The effectivness for the inhibition of oxidation in frozen blackdrum was 0.025% TBHQ (tert-butylhydroquinone) $>$ 1% and 0.5% $\alpha$-tocopherol $>$ water dip $>$ vacuum pack $>$ no dip treatment. Vitamin A was quantifiable but not Vitamin E. No significant change in Vitamin A content was observed in any …
Arch: A Robust Construction Heuristic For The Layout Design Of Food Processing Facilities., George Robert Baskin
Arch: A Robust Construction Heuristic For The Layout Design Of Food Processing Facilities., George Robert Baskin
LSU Historical Dissertations and Theses
A Robust Construction Heuristic (ARCH) represents the first attempt to develop a facilities layout design algorithm tailored to the particular solution of the food processing facility layout problem where a fluctuating product mix due to seasonality or changes in consumer demand is typical. The foundation literature for this research comes predominantly from the industrial engineering, management science, and food science fields. Construction heuristics built layouts from scratch and provided poor quality results. Robustness algorithms had no simplifying heuristics but were reported to yield potentially higher quality layouts than traditional algorithms for layout problems with fluctuating product mixes. ARCH was developed …
Modeling, Simulation, And Automatic Control For Optimum Drying And Storage Of Rough Rice In A Bin System., Jong Hoon Chung
Modeling, Simulation, And Automatic Control For Optimum Drying And Storage Of Rough Rice In A Bin System., Jong Hoon Chung
LSU Historical Dissertations and Theses
A study on modeling, simulation, and automatic control for optimum drying and storage of rough rice in a farm-bin system was conducted to address some aspects of rice post-harvest technology. Resistance-type moisture sensors and temperature and humidity sensors were evaluated for continuously monitoring the conditions of air and grain. Models to predict rice moisture models during drying and storage were developed. Based on accuracy and predictability, the use of the capacitance-type humidity sensor is recommended over the resistance-type moisture sensor. A pressure drop model of airflow through rough rice was developed to aid in determining the optimum size and type …
Cooking Temperature And Antioxidants As Processing Variables Affecting The Flavor And Textural Stability Of Restructured Beef Roasts., Genaro Cortes Arganosa
Cooking Temperature And Antioxidants As Processing Variables Affecting The Flavor And Textural Stability Of Restructured Beef Roasts., Genaro Cortes Arganosa
LSU Historical Dissertations and Theses
The effects of cooking temperature, refrigerated storage, and the presence of sodium tripolyphosphate (STP) and soy protein isolate (SPI) on the development of warmed-over flavor (WOF) in restructured beef roasts were studied. In Phase 1, restructured beef roasts were cooked in a water bath at temperatures of 70, 85 and 100$\sp\circ$C. In Phase 2, four types of roasts containing all combinations of STP and SPI were cooked in a water bath at 70 and 100$\sp\circ$C. The cooked roasts in both phases were then stored at 4$\sp\circ$C for 0 and 3 days. Higher cooking temperatures and longer storage periods tended to …