Food Microbiology Commons^™

Cloning, Expression, And Characterization Of Ara H 3, A Major Peanut Allergen, Cathryn E. Garvey

LSU New Orleans Theses and Dissertations

Abstract There are eight foods that contribute to food allergies in the western world and peanut is the most common. Currently, there are no medical treatments that can cure an individual of food allergy, so avoidance of the allergic food is the only option. In the United States, there are three immunodominant allergic proteins accountable for patient sensitization to peanut, Arachis hypogea 1, 2, and 3 (Ara h 1, Ara h 2, Ara h 3). Therefore, research into why peanuts are more allergic than other foods that have homologous proteins is critical and may be obtained by studying the structural …

Evidence Of Transmission Of Escherichia Coli O157:H7 To The Tissues Or Phyllo-Plane Of Wheat, From Contaminated Soil, Seeds Or Water, Bismarck Antonio Martinez

Department of Food Science and Technology: Dissertations, Theses, and Student Research

Escherichia coli O157:H7 is a human pathogen that can cause a wide spectrum of disease symptoms, such as bloody diarrhea, hemorrhagic colitis, and hemolytic uremic syndrome (HUS). Escherichia coli O157:H7 illness are mainly associated with undercooked beef; however, in recent years outbreaks have been linked to fresh produce such as spinach, lettuce, and sprouts. In 2009, flour was implicated as a contamination source in the consumption of raw cookie dough resulting in 77 illness-cases. The objective of this research was to determine the possible route of transmission of E. coli O157:H7 into the phyllo-plane of wheat using contaminated seed, soil …

Analysis Of Microbial Diversity By Amplicon Pyrosequencing, Ryan Legge

Department of Food Science and Technology: Dissertations, Theses, and Student Research

Microorganisms numerically dominate terrestrial biodiversity, and play important biochemical and geochemical roles in the environments they inhabit. To understand structure and function of complex ecosystems, it is essential to identify primary drivers of microbial diversity and community structure. Historically, the study of microbial ecology was reductive, limited to microbes able to be cultured and enumerated. Microbes meeting this criterion were thought to comprise the dominating members of the environments they were isolated from, however, estimates suggesting up to 99% of the endogenous species are uncultivable with existing methodologies; a concept that reflects experimental failure, rather than a verifiable conclusion. Therefore …

The Trade And Welfare Impacts Of Australian Quarantine Policies: The Case Of Pigmeat, John C. Beghin, Mark Melatos

Department of Agricultural Economics: Faculty Publications

We analyze the trade and welfare impact of quarantine measures imposed by Australia on imports of pigmeat. In particular, we account for changes to Australia’s pigmeat quarantine policy over time, including those changes related to the recent resolution of a WTO dispute between Australia and the European Union. Using a random utility model and applying it to corner solutions in import decisions, tariff equivalents (by major trading partner) are estimated for the different pigmeat quarantine regimes implemented by Australia during the period 1988-2009. The welfare impact on consumers, producers, and foreign exporters is computed using a partial equilibrium model calibrated …

Evaluation Of Prebiotic Fibers And Pectin On Probiotic Strains And Effect Of Bacteriocin-Like Substance On The Survival Of Listeria Monocytogenes, Dolar Pak

Graduate Theses and Dissertations

Probiotics and prebiotics have been shown to provide beneficial effects on the host health and there are numerous research efforts being conducted on a variety of specific applications. However, most prebiotic carbohydrates are lower molecular weight oligosaccharides; and the health benefits of higher molecular weight pectins have not been fully evaluated. According to reviews, pectins are fermented in the large intestine due to the cooperative activities of colonic bacteria with complementary enzymatic activities. There are very few studies that demonstrate the fermentability of high methoxy pectin and low methoxy pectin by pure cultures of human isolates or probiotic bacteria. Thus, …

Lactic Acid Production Using Sweet Potato Processing Waste, Irene Pagana

Graduate Theses and Dissertations

Organic waste generated from industrial sweet potato canning is estimated to be 30% of incoming raw material. This waste contains carbohydrates (sugars and starch) that could be used as substrates for the production of useful compounds via fermentation (e.g. lactic acid), resulting in the production of value-added products. The goal of this research project is to produce a substrate from the sweet potato processing waste material that supports the growth of lactic acid bacteria, which results in the production of lactic acid. The sweet potato waste product was characterized, and found to contain 16.5% solids. The solids components were 18.5% …

The Effect Of Chlorine And Ozone In Controlling Microbes On Organically Grown Cilantro And Carrots, Adam Holtz

BioResource and Agricultural Engineering

This senior project investigates the relative efficacy of ozonated water and chlorinated water for the purpose of sanitizing freshly-harvested organic produce. The aim of this study was to assist the Cal Poly Organic Farm in deciding whether or not to invest in an ozone generator. The crops used for testing were grown organically in the same field. Carrots and cilantro were harvested and promptly treated with 5 ppm ozone solution or 25 ppm sodium hypochlorite solution. Carrots were sampled at 0, 7, and 14 days storage to determine microbial populations. Cilantro was similarly tested at 0, 6, and 12 days …

Sanitation Assessment Of Food Contact Surfaces And Lethality Of Moist Heat And A Disinfectant Against Listeria Strains Inoculated On Deli Slicer Components, Sabelo Muzikayise Masuku

Graduate Theses and Dissertations

The overall objectives of this study were to: evaluate the efficacy of different cleaning cloth types and cloth-disinfectant combinations in reducing food contact surface contamination to acceptable levels; determine the optimum moist heat and moist heat + sanitizer treatments that can significantly reduce the number of Listeria strains on deli slicer components; and investigate if the moist heat treatment used in this study induced the viable-but-non-culturable (VBNC) state in Listeria cells. The efficacy of wiping cloths was measured using ATP-bioluminescence and total plate count methods using four different wiping cloths and silver dihydrogen citrate sanitizer on food contact surfaces. The …

Effect Of Enzymatic Treatments On The Physiochemical Properties Of Different Corn Starches, Curtis Robert Luckett

Graduate Theses and Dissertations

Amylose readily reassociates to form films and crystalline structures that are resistant to digestion by amylolytic enzymes and known as resistant starch type III (RS3). This study investigated the RS3 formation and cereal coating properties from enzyme-modified corn starches with varying amylose contents, including Hylon VII (70% amylose), Hylon V (50% amylose), and common corn (25% amylose). For RS3 formation, corn starches were first gelatinized and then hydrolyzed using β-amylase to varying degrees. The resultant hydrolyzed starch was debranched with isoamylase and then exposed to 3 times of temperature cycling at 135/133/133°C for 30 min and 95°C for 24 hr …

Validation Of Thermal Processing To Control Salmonella Spp. And Clostridium Perfringens During Prime Rib Preparation From Intact And Non-Intact Meat, Maria A. Calle

Department of Food Science and Technology: Dissertations, Theses, and Student Research

Beef prime rib is a delicacy cooked at low temperatures for long period and extended hot holding prior to consumption. Due to the potential survival and outgrowth of foodborne pathogens, this process may pose a public health risk. Considering an increase in the availability of non-intact beef, the microbial safety of the preparation of prime rib from intact and mechanically tenderized beef was evaluated.

In the first study, lethality of the prime rib (from intact and non-intact, blade tenderized beef) cooking process to Salmonella spp. was evaluated. Boneless beef rib eye was surface inoculated with a five-strain cocktail of Salmonella …

Role Of Lactic Acid Bacteria As A Bio-Sanitizer To Prevent Attachment Of Listeria Monocytogenes On Deli Slicer Contact Surfaces, And The Influence Of Listeria Innocua On The Attachment Of L. Monocytogenes On Selected Materials Located In The Food-Processing Environment, Jean Baptiste Ndahetuye

Graduate Theses and Dissertations

Listeria monocytogenes an important foodborne pathogen that continues to be a serious problem for the food industry. This pathogen contaminates food primarily during post-harvest in the food-processing environment. Its ecology in the food-processing environment is not well understood but previous research has demonstrated the ability of L. monocytogenes to survive on food contact surfaces after cleaning and disinfection. The current study explored the attachment of three lactic acid bacteria (LAB) strains, Lactobacillus animalis , Lb. amylovorus and Pediococcus acidilactici , their combination in a cocktail, and their influence to prevent the attachment of L. monocytogenes at room temperature by examining …

Feed Supplementation With Natural Extracts Of Cranberry And Its Efficacy On Campylobacter Colonization In Poultry, Ann Woo-Ming

Graduate Theses and Dissertations

Campylobacter spp. has been identified as one of the leading causative agents of food borne diarrheal illness. Epidemiological evidence has shown that poultry is the main source for human infection. Poultry are asymptomatic carriers of Campylobacter within their gastrointestinal tract, with colonization levels reaching 106-108 cfu/g cecal content. Surveys of domestic poultry flocks have estimated that approximately 90% of flocks are positive for Campylobacter colonization. Risk assessment studies have determined that by reducing levels of Campylobacter colonization during rearing, incidences of human infection will be significantly reduced. Currently there are no consistently effective treatments to eliminate Campylobacter from poultry flocks. …

Biological Strategies And Mathematical Approaches For Limiting Bacterial Contaminants And Chemical Pollutants In Bioethanol Fermentations, Alia Chahed Ep Limayem

Graduate Theses and Dissertations

During the most recent decades increased interest in fuel from biomass in the United States and worldwide has emerged each time petroleum derived-gasoline registered well publicized spikes in price. The willingness of the U.S. government to face the issues of more heavily high-priced foreign oil and climate change has led to more investment on plant-derived sustainable biofuel sources. Biomass derived from corn has become one of the primary feedstocks for bioethanol production for the past several years in the U.S. However, the argument of whether to use food as biofuel has led to a search for alternative non-food sources. Consequently, …

Response Surface Methodology Approach For The Optimization Of Lab Fermentation Using Vegetable Based Substrate, Amit Jaiswal, Nissreen Abu-Ghannam, Juan Valverde

Conference papers

In the present studies, an attempt was made to optimize the conditions for the lactic acid bacteria (LAB) fermentation using Irish York cabbage (Brassica oleracea var. capitata alba subvar. conica) as a substrate. Prior to fermentation with Lactobacillus plantarum, York cabbage was blanched at 95°C for 12 min to inactivate surface microflora. To achieve an optimal fermentation condition which would result in higher release of phytochemicals and antioxidant capacity in the broth, Box-Behnken design integrating a desirability approach was used. The optimized factors (fermentation time 36h, solid/liquid ratio 0.25 g/ml and agitation rate 100 rpm) were used for …

Delicious-Ology: The Science Of Delicious Food, Sasha Yan

Undergraduate Theses—Unrestricted

You can read this book two ways. If you want to “just cook,” flip to the recipe index, pick a recipe, and skip straight to that page. The surrounding text will explain some aspects of the science behind the recipe. While the recipes in this book are chosen to complement and provide examples of the science, they’re also recipes that are fantastic in and of themselves.

Detection And Identification Of Salmonella Enterica, Escherichia Coli, And Shigella Spp. Via Pcr-Esi-Ms: Isolate Testing And Analysis Of Food Samples, Sarah E. Pierce, Rosalee S. Hellberg, Chorng-Ming Cheng, Kai-Shun Chen, Donna M. Williams-Hill, William B. Martin, Marc W. Allard

Food Science Faculty Articles and Research

An assay to identify the common food-borne pathogens Salmonella, Escherichia coli, Shigella, and Listeria monocytogenes was developed in collaboration with Ibis Biosciences (a division of Abbott Molecular) for the Plex-ID biosensor system, a platform that uses electrospray ionization mass spectroscopy (ESI-MS) to detect the base composition of short PCR amplicons. The new food-borne pathogen (FBP) plate has been experimentally designed using four gene segments for a total of eight amplicon targets. Initial work built a DNA base count database that contains more than 140 Salmonella enterica, 139 E. coli, 11 Shigella, and 36 Listeria patterns and 18 other Enterobacteriaceae organisms. …

Antimicrobial Efficacy Of Edible Soy Protein Isolate Films And Coatings Incorporated With Hop Ethanol Extract And The Influence On Shelf-Life And Sensory Attributes Of Bologna, Jamie R. G. Skudlarek

Theses and Dissertations--Animal and Food Sciences

There is demand for improved security of refrigerated ready-to-eat meats. Antimicrobial edible films and coatings could function as an added barrier against post-processing contamination. Hops and hop extracts are known for their antimicrobial efficacy which is attributed to key antimicrobial components including humulones, lupulones, xanthohumol and various terpenoids. Yet, hop ethanol extract has not been studied as an antimicrobial to incorporate into edible protein films and/or coatings. The overall objective of this research was to evaluate hop ethanol extract as an antimicrobial agent incorporated into edible soy protein isolate (SPI) films and coatings, and the influence on the shelf-life and …

Recent Advances In The Application Of Non Thermal Methods For The Prevention Of Salmonella In Foods, Shilpi Gupta, Nissreen Abu-Ghannam

Books/Book Chapters/ Proceedings

Food-borne illness as a result of consumption of foods contaminated with pathogenic bacteria is a world-wide concern. The presence and subsequent growth of micro-organisms in food in addition to improper storage not only results in spoilage but also in a reduction of food quality. The microbiological safety in ready to eat products is a cause of big concern not only for the consumers and food industries but also for the regulatory agencies. The number of documented outbreaks of foodborne diseases has increased in the last decade with Salmonella spp., Listeria monocytogenes and Escherichia coli being responsible for the largest number …

Evaluation Of Novel Low Molecular Weight Antimicrobial Compounds Produced By Lactic Acid Bacteria., Jiahui Leona Guo

Theses

Fungal food spoilage plays a pivotal role in the deterioration of food and feed systems and some fungi are also able to produce compounds toxic for humans and animals. The mycotoxins produced by fungi can cause serious health hazards and include toxins which are cancerogenic, immunotoxic, teratogenic, neurotoxic, nephrotoxic or hepatotoxic effects and Kashin-Beck disease. In addition to this, fungal spoilage/pathogens cause losses of marketable quality and hygiene of foodstuffs, resulting in major economic problem throughout the world. Nowadays, food spoilage can be prevented using physical and chemical methods, but no efficient strategy has been proposed so far to reduce …

Optimization Of Lactic Acid Fermentation Of York Cabbage For The Development Of Potential Probiotic Products, Amit Jaiswal, Shilpi Gupta, Nissreen Abu-Ghannam

Articles

In the present study, York cabbage was used as the sole substrate for the lactic acid (LA) fermentation with Lactobacillus plantarum. York cabbage was blanched at 95°C for 12min to inactivate surface microflora prior to fermentation. To achieve an optimal fermentation condition which would result in higher release of phytochemicals and antioxidant (AO) capacity in the broth, Box-Behnken design integrating a desirability approach was used. A second-order polynomial equation was developed indicating the effect of solute/liquid ratio, agitation rate and fermentation time on desired parameters. The optimized factors were used for fermenting York cabbage to obtain maximum bacterial growth, …

Antimicrobial, Antioxidant And Free Radical-Scavenging Capacity Of Brown Seaweed Himanthalia Elongata From Western Coast Of Ireland, Gaurav Rajauria, Amit Jaiswal, Nissreen Abu-Ghannam, Shilpi Gupta

Articles

Water,methanol and mixtures (20–80%) thereof have been used for the extraction of phenolic compounds from Irish brown seaweed Himanthalia elongata for studying its antimicrobial and antioxidant properties.The 60%methanolic extract exhibited significantly (P < 0.05) the highest value of yield (6.8 6 0.24%), total phenol (286.0 6 4.61 mg gallic acid equivalents/g), flavonoid (109.8 6 2.68 mg quercetin equivalents/g) and condensed tannin content (35.6 6 1.03 mgcatechin equivalents/ g). Antimicrobial activity of 60% methanolic extract tested from disc diffusion and broth dilution methods was effective against various food spoilage and pathogenic bacteria studied.The same extract exhibited statistically highest reducing power and antioxidant capacity againstDPPHradical,metal ions, lipid peroxides and hydrogen peroxide radicals. The UV-visible spectroscopy showed absorption maxima at 205 and 260 nm and the presence of hydroxyl group (3,431 cm-1) and an aromatic ring (around 1,465, 1,505 and 1,624 cm-1) in Fourier Transform Infrared spectroscopy, suggested the presence of phenolic compounds in the extract.