Food Microbiology Commons^™

Four Legs Good, Two Legs Bad: How Slaughterhouse Safety Hasn’T Kept Up With The Times, Emily Ziemski

Capstones

From legal loopholes and outdated rules to undetectable infections and understaffing, the United States Department of Agriculture may not be doing all it can to make sure the American public’s health isn't at risk. As the people of the United States consume over 500 million pounds of beef a year, food safety policy and slaughterhouses are falling behind in proper procedural measurements in the beef industry.

emziemski.com/capstone

Radiofrequency Processing For Inactivation Of Salmonella Spp. And Enterococcus Faecium Nrrl B-2354 In Whole Black Peppercorn And Ground Black Pepper, Xinyao Wei

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

Black pepper has been implicated in several foodborne illness outbreaks and food product recalls due to Salmonella contamination. Conventional decontamination methods for black pepper are challenged by harmful residues or quality deterioration. Radiofrequency (RF) heating reduces the come-up time which allows to design a high-temperature short-time processing to inactivate Salmonella with minimal deterioration in product quality. The objectives of this study were to investigate RF heating for inactivation of Salmonella in whole black peppercorn and ground black pepper samples, evaluate Enterococcus faecium NRRL B-2354 as a surrogate for Salmonella, and assess quality deterioration during RF heating of whole black peppercorn …

Effects Of Pre-Chiller Temperature On The Microbial Ecology Of Whole Bird Carcass Rinses, Rachael Elizabeth Blevins

Graduate Theses and Dissertations

Upon entering a poultry processing facility, birds are already contaminated with a variety of microorganisms. It is the responsibility of the processor to reduce these numbers to deliver a wholesome product to customers. This is not an easy task as there are ample opportunities for further microbial contamination. Some of these opportunities are obvious. For example, any areas where contaminants could be washed off one bird and onto another are always an area for concern, i.e. the scalder or the chiller. There are numerous opportunities for contamination that are not so obvious. These incidents of contamination are not necessarily due …

Experimental Approaches To Understand And Control Salmonella Infection In Poultry, Yichao Yang

Graduate Theses and Dissertations

Salmonella is a major foodborne pathogen around the world and chickens are the major reservoir to transmit Salmonella into the human food chain. For decreasing the infection of Salmonella, we developed six attenuated live vaccines based on Salmonella Enteritidis (SE) and Typhimurium (ST) for testing the cross-serovar and cross-serogroup protection from the challenge of Salmonella Heidelberg and Campylobacter jejuni. One of the constructed vaccine strain showed ability to protect against challenge from Salmonella Heidelberg. Even though some preventive approaches are able to decrease Salmonella colonization in the gastrointestinal tract of chickens or other farm animals, Salmonella transmission mechanisms remain unclear. …

Role Of Incompatibility Group 1 (Inci1) Plasmid-Encoded Factors On Salmonella Enterica Antimicrobial Resistance And Virulence, Pravin Raghunath Kaldhone

Graduate Theses and Dissertations

Foodborne illnesses are a leading cause of infectious diseases in the world. Among enteric organisms Salmonella is a key pathogen. It’s high prevalence in poultry and other food-animal sources make it imperative to study. Salmonella has the ability to modify its genetic content with help of mobile genetic elements such as plasmids. Incompatibiltiy group 1 (IncI1) plasmids are commonly reported in Salmonella. This study evaluates role on IncI1 plasmids in antimicrobial resistance and virulence in Salmonella. Genetic determinants of resistance and virulence are noted among our IncI1-containing Salmonella isolates. These genetic elements are also transferable and reported to carry respective …

Evaluation Of The Impact Of Tart Cherries Polyphenols On The Human Gut Microbiota And Phenolic Metabolites In Vitro And In Vivo, Alba Claudia Mayta-Apaza

Graduate Theses and Dissertations

Tart cherries are polyphenol abundant stone fruits claimed to exert health benefits further of its nutritional properties. The abundant phytochemicals content in tart cherries also referred as dietary polyphenols have been considered as an effective natural antioxidant when added in daily diet. However, it has been hypothesized the intervention of gut microbiota on the overall functionality of such compounds. This thesis contains a wide-ranging literature review focused on tart cherry as a crop, current market, functional food, and several health benefits. Furthermore, the research done describes and in vitro and in vivo assays of a short-term dietary intervention of tart …

Evaluating The Effect Of Chitosan, Water-Soluble Chitosan And Chitosan Application Techniques On The Quality Of Refrigerated Catfish Fillets, Franklin Bonilla Torres

LSU Master's Theses

Chitosan (CH) is a biopolymer synthetized by deacetylation of chitin, it is found in the exoskeleton of crustaceans, cell wall of fungi, and insects. CH’s water insolubility limited the used of this compound in some food systems. However, enzymatic hydrolysis of CH yields water-soluble chitosan (WSC). The aim of this study was to evaluate the effect of chitosan, water-soluble chitosan, and chitosan application techniques on the quality of refrigerated catfish fillets. This research was conducted in two separated studies. In the first study, three solution treatments were prepared: (1) a 1% acetic acid (AA) solution, (2) a 0.5% CH solution …

Effect Of Hot Water Conditioning On Microbial Safety And Quality Of In-Shell Pecans, Karuna Kharel

LSU Master's Theses

Hot water conditioning of in-shell pecans is one common practice followed by industries to facilitate shelling. It also acts as a preventive control for potential microbiological contamination that might occur during pre- and post-harvest processes. However, heat treatment may have an effect on the eating quality of nuts. The main objectives of the study were to develop a post-harvest hot water treatment intervention as a kill step to destroy foodborne pathogens on in-shell pecans and evaluate the effect of treatments on physicochemical properties, consumer acceptance and purchase intent of dehulled and roasted pecans. The time (1-5 min) and temperature (70, …

Heat, Acid And Osmotic Stress Tolerance Of Leuconostoc Mesenteroides As Influenced By Prior Exposure To Various Mild Stress Conditions, Ingrid C. Osorio Rodriguez

LSU Master's Theses

The importance of Leuconostoc mesenteroides is recognized for its contribution to taste in cultured dairy products. It has been cited for its potential role as a probiotic. Consumer demand exists for new dairy products with health benefits. In the manufacture of probiotic-products survival of Leuconostoc mesenteroides would depend on its ability to tolerate challenging processing and storage conditions. Improved viability by prior exposure to mild stresses can increase stress tolerance toward a more severe stress. Furthermore, it can result in cross-protection due to connection of several proteins in response to stresses. Objective was to evaluate the effect of prior …

Hybrid Extended Kalman Filtering And Noise Statistics Optimization For Produce Wash State Estimation, Vahid Azimi, Daniel Munther, Seyed Abolfazl Fakoorian, Thang Tien Nguyen, Daniel J. Simon

Mathematics and Statistics Faculty Publications

Food-borne diseases associated with fresh produce consistently cause serious public health issues. Although sanitization measures are utilized to enhance the safety of fresh produce, strategies that neglect the dynamic nature of commercial wash processes are limited, creating the potential for pathogen cross-contamination and major disease outbreaks. In light of this risk, there is an urgent need for new control approaches during produce washing to reduce the probability of outbreaks. As an important step in this direction, a hybrid extended Kalman filter (HEKF) and particle swarm optimization (PSO)-based noise statistics optimization are designed for a produce wash system. The HEKF uses …

Interaction Of Cocoa Powder With Intestinal Microbiota, Martha M. Escoto Sabillon

LSU Master's Theses

Cocoa is the fully fermented and dried seed of the cacao tree (Theobroma cacao L.) which has prebiotic properties, due to their high concentration of polyphenols. Therefore, the ingestion of cocoa could cause changes in the proportions of the intestinal microbiota that can influence the intestinal immune response. The objective of this study was to determine the effect of alkalization process of the cocoa bean in the diversity of the gut microbiota. The samples were “lavado” unprocessed cocoa powder, “natural” unprocessed cocoa powder, “D-11-S” as alkalized cocoa powder, “D-11-B” heavily alkalized cocoa powder, and raw cocoa “shells” and a control …

Isolation, Detection, And Prevention Of Foodborne Bacteria In Irrigation Water And Dairy Food, Mohammed Saleemallah Alhejaili

LSU Doctoral Dissertations

Foodborne microorganisms can be beneficial to humans or cause disease. Salmonella is one of the most causative foodborne disease outbreaks in the U.S.A. Salmonella has been detected in surface water used in irrigation, and can survive for weeks to years in water. The purpose of the study was to detect low levels of Salmonella spp. by comparing surfactant modified zeolite (SMZ) filtration and Activated Carbon (AC) filtration with the Environmental Protection Agency (EPA) method 1200. Also, to determine the generic E.coli counts and if there was a direct correlation of Salmonella to generic E. coli in irrigation water. The EPA …

Is Tb Testing Associated With Increased Blood Interferon-Gamma Levels?, Aideen E. Kennedy, Jim O'Mahony, Noel Byrne, John Macsharry, Riona G. Sayers

Department of Biological Sciences Publications

The Republic of Ireland reports a relatively low prevalence of Johne’s disease (JD) compared to international counterparts. Postulated reasons for this include a lower average herd size and a grass-based production system. Ireland also engages in high levels of bovine tuberculosis (bTB) testing. As interferon-gamma (IFN-γ) is believed to play a key role in protecting against JD, it is our hypothesis that administration of purified protein derivative (PPD), as part of the bTB test, is associated with a systemic increase in IFN-γ production, which may potentially limit clinical progression of the disease. We studied 265 cows (202 Friesian and 63 …

A Preliminary Study To Evaluate Issues Involved Under In Vivo Conditions Of A Delivery System Containing Immobilized Lactobacillus Plantarum Ncimb 8826 On Rice Bran Fiber Extract, Chen Liu

LSU Master's Theses

Gut diseases like diarrhea, irritable bowel symptoms, and inflammatory bowel disease (IBD) can be treated with probiotics therapy. Probiotics have been recognized for their ability to promote the development of gut health and improve immune system. However, a difficulty involved with the use of probiotics is the need for and the ability to deliver a sufficient concentration of viable probiotic to the appropriate site. This can be difficult since the most common (and probably easiest) method of delivering the probiotic is orally. As such, the probiotic must be capable of surviving the hostile conditions of passage through the G.I. tract. …

Phylogenetic Diversity Of The Bacterial Communities In Craft Beer, Lindsey Rodhouse

Graduate Theses and Dissertations

The craft beer industry is increasing in popularity in the United States. The craft brewing process typically does not use a pasteurization step, therefore the boiling process is the primary critical control step. Any microorganisms introduced after boiling, or those that are not killed during boiling, are likely to participate in fermentation and persist in the final product. Previous culture-based studies have isolated bacteria and yeast from craft beers at specific time points, but little research has been done on the process as a whole. The objectives of this research are to (1) track bacteria development throughout the brewing process …

Validation Of Extrusion Processing For The Safety Of Low-Moisture Foods, Tushar Verma

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

Salmonella in low-moisture foods is an emerging challenge due to numerous food product recalls and foodborne illness outbreaks. The new Food Safety Modernization Act requires the food processors to validate their process controls that indeed kills the desired number of bacteria. This research had two major objectives: 1) Develop a response surface model for Salmonella inactivation during the extrusion of low-moisture food 2) Evaluate the use of Enterococcus faecium NRRL B-2354 as an adequate surrogate for Salmonella during the extrusion of low-moisture food. Oat flour was selected as a low-moisture food model. For inoculation, cocktail of five different strains of …

Modeling The Survival Of Salmonella In Soy Sauce-Based Products Stored At Two Different Temperatures, Ana Cristina Arciniega Castillo

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

Acidified foods are defined in the regulations as “low acid foods to which acid(s) has been added to bring finished pH to 4.6 or below”. As the market for these products expands, an increasing number of them are being processed with reduced heat treatment, relying on acid alone to ensure the destruction of pathogens. When considering the survival rate of microbial pathogens in these products, pH, water activity, temperature, salt content and holding time are integral and must be considered together.

Despite improvements in production, handling, and distribution of food products in recent years, protecting consumers from foodborne illness still …

Persistence Of Enteric Viruses On Surfaces Under Varying Environmental Conditions, Nicole L. Turnage

Graduate Theses and Dissertations

Human enteric viruses such as human norovirus (hNoV) and Aichivirus A (AiV) are common foodborne viruses with hNoVs being identified as the leading causative agent of foodborne illnesses in the U.S. Moreover, hNoVs have been identified as the leading cause of nonbacterial acute gastroenteritis in the U.S. and worldwide. Fomite surface contamination is a major transmission route for enteric viruses. The application of an optimized virus recovery method from fomites is essential for better understanding of virus persistence under varying environmental conditions (EC). This study aimed to optimize a surface sampling method for virus recovery from nonporous food contact surfaces …

The Recovery Of Protein From Egg Yolk Protein Extraction Granule Byproduct, Irene Jennifer Kaufman

Master's Theses

In addition to proving an excellent source of nutrients, eggs are used in the food, cosmetic, and biotechnology industries for their rheological and bioactive properties. Much of the potential for the added value is in individual components of the egg, rather than the whole egg. At low speed centrifugation, yolk separates into two distinct fractions—granules and plasma. It is becoming increasingly popular in the industry to remove the plasma fraction of the egg yolk to use for its livetins, particularly immunoglobulin Y, leaving behind a granule by-product (“yellow cake”). Previous research has shown potential added-value from the granule fraction, especially …

Knowledge Of Food Safety And Food Handling Practices Amongst Food Handlers In The Republic Of Ireland, Nora A. Moreb, Anushree Priyadarshini, Amit Jaiswal

Articles

Food safety concerns have existed for a long time, as millions of people across the globe suffer from food borne disease every year. Contamination of food owing to limited knowledge of food safety practices primarily increases the risk of food borne illnesses. In the present study, quantitative research was carried out to gauge the level of food safety knowledge amongst people living in Ireland. A total of 1069 participants from all over the Republic of Ireland contributed to the survey (of which 821 were included in this research). Results showed that the residents of Ireland overall had an average levelonknowledge …