Food Microbiology Commons^™

Temperature Stability And Effectiveness Of Plasma-Activated Liquids Over An 18 Months Period, Evanthia Tsoukou, Paula Bourke, Daniela Boehm

Articles

Non-buffered plasma-activated liquids such as water and saline have shown bactericidal effects. In the present study, we investigated the anti-bacterial efficacy and stability of plasma-activated water (PAW) and plasma-activated saline (PAS), generated using a high voltage dielectric barrier discharge system. This study compares the potential of non-buffered plasma-activated liquids (PAL) for the inactivation of Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) after storage of the solutions at five different temperatures for a storage time up to 18 months after their generation. The temperatures used were room temperature, 4 °C, −16 °C, −80 °C, −150 °C. Both PAW and …

Food Security And Diet Quality In Native Hawaiian, Pacific Islander, And Filipino Infants 3 To 12 Months Of Age, Sally Campbell, John J. Chen, Carol J. Boushey, Heather Eicher-Miller, Fengqing Zhu, Marie K. Fialkowski

Articles

Food insecurity and other nutritional risks in infancy pose a lifelong risk to wellbeing; however, their effect on diet quality in Native Hawaiian, Pacific Islander, and Filipino (NHPIF) infants in Hawai‘i is unknown. In this cross-sectional analysis, the association between various indicators of food security and NHPIF infant diet quality were investigated in 70 NHPIF infants aged 3–12 months residing on O‘ahu, Hawai‘i. The dietary assessments of the infants were collected using a mobile food record^TM. Foods consumed across four days were categorized into seven food groups. Indicators for food security were examined through an adapted infant food …

Effect Of Atmospheric Cold Plasma On The Functional Properties Of Whole Wheat (Triticum Aestivum L.) Grain And Wheat Flour, Sonal Chaple, Chaitanya Sarangapani, John B. Jones, Ed Carey, Lucie Causeret, Annaik Genson, Brendan Duffy, Paula Bourke

Articles

Atmospheric cold plasma (ACP) has emerged as a novel processing technology, with demonstrated efficiencies in microbial inactivation. However, studies on the effects of ACP and potential to modify the functional properties of foods are sparse. The objective of this study is to determine the effect of ACP on physico-chemical and functional properties of wheat flour. In this study, both whole wheat grains and wheat flour were subjected to a dielectric barrier discharge (DBD) contained plasma reactor for a range of treatment times (5–30 min) at 80 kV. Plasma treatment increased the flour hydration properties of wheat flour. Rapid visco-analyser results …

Development Of A Selective Inhibitor For Kv1.1 Channels Prevalent In Demyelinated Nerves, Ahmed Al-Sabi, Declan Daly, Myles Rooney, Cian Hughes, Gemma K. Kinsella, Seshu Kaza, Kieran Nolan, J. Oliver Dolly

Articles

Members of the voltage-gated K+ channel subfamily (Kv1), involved in regulating transmission between neurons or to muscles, are associated with human diseases and, thus, putative targets for neurotherapeutics. This applies especially to those containing Kv1.1 α subunits which become prevalent in murine demyelinated axons and appear abnormally at inter-nodes, underlying the perturbed propagation of nerve signals. To overcome this dysfunction, akin to the consequential debilitation in multiple sclerosis (MS), small inhibitors were sought that are selective for the culpable hyper-polarising K+ currents. Herein, we report a new semi-podand – compound 3 – that was designed based on the modelling of …

Formation Of Escherichia Coli O157: H7 Persister Cells In The Lettuce Phyllosphere And Application Of Differential Equation Models To Predict Their Prevalence On Lettuce Plants In The Field, Daniel S. Munther, Michelle Q. Carter, Claude V. Aldric, Renata Ivanek, Maria T. Brandl

Mathematics and Statistics Faculty Publications

American Society for Microbiology. Escherichia coli O157:H7 (EcO157) infections have been recurrently associated with produce. The physiological state of EcO157 cells surviving the many stresses encountered on plants is poorly understood. EcO157 populations on plants in the field generally follow a biphasic decay in which small subpopulations survive over longer periods of time. We hypothesized that these subpopulations include persister cells, known as cells in a transient dormant state that arise through phenotypic variation in a clonal population. Using three experimental regimes (with growing, stationary at carrying capacity, and decaying populations), we measured the persister cell fractions in culturable EcO157 …

How Fishy Is Your Fish? Authentication, Provenance And Traceability In Fish And Seafood By Means Of Vibrational Spectroscopy, Aoife Power, Daniel Cozzolino

Articles

Food authenticity, traceability and provenance are emerging issues of major concern forconsumers, industries and regulatory bodies worldwide. In addition, both food safety and securityare an intrinsic component of food quality where the above issues are key in modern traceabilityand management systems. It has been reported that substitution of a high-quality species by lessexpensive ones might be a frequent practice in seafood products such as fish and shellfish. In thistype of products, the source (e.g., origin) and identification of the species are complex. Althoughdifferent countries have implemented strict regulations and labelling protocols, these issues still are ofconcern. This article briefly reviews …

Evaluation Of Salmonella Enteritidis And Escherichia Coli O157:H7 Volatile Organic Compound Analysis For Food Safety Monitoring: A Preliminary Study, Jessica E. Lemley

Graduate Theses, Dissertations, and Problem Reports (ETD)

Food borne illness has the potential to impact every point of production from producers to consumers. Food product recalls are common due to the presence of food borne illness causing bacteria. Detection of volatile organic compounds (VOC) have the potential to reduce the number of illnesses and recalls through application of additional monitoring of food products like those most commonly recalled. The objective of this research was to 1) explore the use of closed-loop headspace analysis coupled with gas chromatography-mass spectrometry (GC-MS) on food borne illness causing bacteria and 2) examine the VOC profile of Escherichia coli serotype O157:H7 in …

The Exploration Of Nanotoxicological Copper And Interspecific Saccharomyces Hybrids, Matthew Joseph Winans Phd

Graduate Theses, Dissertations, and Problem Reports (ETD)

Nanotechnology takes advantage of cellular biology’s natural nanoscale operations by interacting with biomolecules differently than soluble or bulk materials, often altering normal cellular processes such as metabolism or growth. To gain a better understanding of how copper nanoparticles hybridized on cellulose fibers called carboxymethyl cellulose (CMC) affected growth of Saccharomyces cerevisiae, the mechanisms of toxicity were explored. Multiple methodologies covering genetics, proteomics, metallomics, and metabolomics were used during this investigation. The work that lead to this dissertation discovered that these cellulosic copper nanoparticles had a unique toxicity compared to copper. Further investigation suggested a possible ionic or molecular mimicry …

Assessing The Biological Safety Of Atmospheric Cold Plasmatreated Wheat Using Cell And Insect Models, Agata Los, Dana Ziuzina, Daniela Boehn, Paula Bourke

Articles

Atmospheric cold plasma (ACP) is under investigation for an extensive range of biocontrol applications in food biosystems. However, the development of a novel intervention technology requires a thorough evaluation of the potential for negative effects and the implications for the human and animal food chains’ safety. The evaluations were performed using a contained, high-voltage, dielectric barrier discharge plasma system. The cytotoxicity of two types of food models—a liquid model (wheat model medium (WMM)) vs. a solid model (wheat grain extract (WGE)) was compared in vitro using the mammalian cell line CHO-K1. The residual toxicity of ACP treatment of grains for …

Marine Toxins Targeting Kv1 Channels: Pharmacological Tools And Therapeutic Scaffolds, Rocio K. Finol-Urdaneta, Aleksandra Belovanovic, Milica Micic-Vicovac, Gemma K. Kinsella, Jeffrey R. Mcarthur, Ahmed Al-Sabi

Articles

Toxins from marine animals provide molecular tools for the study of many ion channels, including mammalian voltage-gated potassium channels of the Kv1 family. Selectivity profiling and molecular investigation of these toxins have contributed to the development of novel drug leads with therapeutic potential for the treatment of ion channel-related diseases or channelopathies. Here, we review specific peptide and small-molecule marine toxins modulating Kv1 channels and thus cover recent findings of bioactives found in the venoms of marine Gastropod (cone snails), Cnidarian (sea anemones), and small compounds from cyanobacteria. Furthermore, we discuss pivotal advancements at exploiting the interaction of κM-conotoxin RIIIJ …

Characterization Of Antimicrobial Effects Of Plasma-Treated Water (Ptw) Produced By Microwave-Induced Plasma (Midiplexc) On Pseudomonas Fluorescens Biofilms, Oliver Handorf, Viktoria Isabella Pauker, Thomas Weihe, Eric Freund, Sander Bekeschus, Katharina Riedel, Uta Schnabel, Jörg Ehlbeck

Articles

stract: For the decontamination of surfaces in the food production industry, plasma generated compounds (PGCs) such as plasma-treated water (PTW) or plasma processed air (PPA) offer many promising possibilities for future applications. Therefore, the antimicrobial effect of water treated with microwave-induced plasma (MidiPLexc) on Pseudomonas fluorescensbiofilms was investigated. 10 ml deionized water was treated with the MidiPLexc plasma source for 100 s, 300 s and 900 s (pre-treatment time) and the bacterial biofilms were exposed to the PTW for 1 min, 3 min and 5 min (post treatment time). To investigate the influence of PTW on P. fluorescensbiofilms, microbiological assays …

Cold Atmospheric Plasma Stimulates Clathrin-Dependent Endocytosis To Repair Oxidised Membrane And Enhance Uptake Of Nanomaterial In Glioblastoma Multiforme Cells, Zhonglei He, Kangze Li, Laurence Scally, Eline Manaloto, Sebnem Gunes, Sing Wei Ng, Marcus Maher, Brijesh Tiwari, Hugh Byrne, Paula Bourke, Furong Tian, Patrick J. Cullen, James Curtin

Articles

Cold atmospheric plasma (CAP) is increasingly studied in a growing number of clinical trials for cancer treat-ment1,2 and research is ongoing to explore the combination of CAP with other therapies, including nanoparticles, radiotherapy and chemotherapy3–5.Gold nanoparticles (AuNPs) are known to be weakly-toxic to human cells and be readily manufactured and designed for targeting delivery of various therapeutic compounds into cells. Citrate-capped cationic AuNPs may adsorb serum proteins onto their surface and thereby stimulate receptor-mediated endocytosis6. Without special surface functionalisation, AuNPs enter cells and become trapped in vesicles6–8 or enter the nucleus, depending on their size/shape9,10. Meanwhile, AuNPs with functionalised surface …

Effects Of Cold Atmospheric Plasma On Mackerel Lipid And Protein Oxidation During Storage, Juan M. Pérez-Andrés, María De Alba, Sabine M Harrison, Nigel P. Brunton, Patrick J. Cullen, Brijesh K. Tiwari

Articles

The present study investigated the effects of cold atmospheric plasma on the shelf-life stability of lipids andproteins of commercially packaged mackerelfillets. The results showed no significant effects on lipid oxidationbetween the control samples and those treated at 80 kV for extended treatment times of 5 min using an in-package plasma system. In addition, no significant changes (p > 0.05) were found in the fatty acid compositionor nutritional quality indices after treatment. Finally, the formation of carbonyls was accelerated by plasmatreatment at the end of the storage period for 4 °C and 8 °C. These results suggest that cold atmospheric plasmatechnologies are …

Effects Of Cold Plasma On Wheat Grain Microbiome And Antimicrobial Efficacy Against Challenge Pathogens And Their Resistance, Agata Los, Dana Ziuzina, Daniela Boehm, Paula Bourke

Articles

The safety and quality of cereal grain supplies are adversely impacted by microbiological contamination, with novel interventions required to maximise whole grains safety and stability. The microbiological contaminants of wheat grains and the efficacy of Atmospheric Cold Plasma (ACP) for potential to control these risks were investigated. The evaluations were performed using a contained reactor dielectric barrier discharge (DBD) system; samples were treated for 0–20 min using direct and indirect plasma exposure. Amplicon-based metagenomic analysis using bacterial 16S rRNA gene and fungal 18S rRNA gene with internal transcribed spacer (ITS) region was performed to characterize the change in microbial community …

The Effect Of Lauric Arginate On The Thermal Inactivation Of Starved Listeria Monocytogenes In Sous-Vide Cooked Ground Beef, Vijay K. Juneja, Marangeli Osoria, Uma Tiwari, Xinran Xu, Chase E. Golden, Sudarsan Mukhopadhyay, Abhinav Mishra

Articles

The aim of this study was to examine the efficacy of lauric arginate (LAE, 1000 ppm – 3000 ppm) as an assisting tool to reduce starved Listeria monocytogenes population in ground beef following sous-vide processing at different temperatures (55–62.5 °C). Ground beef mixed with LAE was vacuum sealed and a laboratory water bath was used for sous-vide cooking. Loglinear and Weibull models were fit to the survival microbial population and the D and Z-values were determined at 55–62.5 °C. Calculated D-values ranged from 33.62 to 3.22 min at temperature 55–62.5 °C. LAE at higher concentration is an effective antimicrobial to …

Changes In Chemical And Microbiological Quality Of Semi-Processed Black Soldier Fly (Hermetia Illucens L.) Larval Meal During Storage, E. Kamau, C. Mutungi, J. Kinyuru, S. Imathiu, S. Ekesi, S. Ekesi, D. Nakimbugwe, K. K.M. Fiaboe

All Peer-Reviewed Publications

Edible insects are receiving attention as a protein source in the food and feed sector. However, successful commercialisation requires mass production matched with appropriate processing and storage techniques. The quality of dried and pulverised black soldier fly larvae stored in woven polypropylene (PP) sacks, polyethylene (PE) bags and plastic containers with screw lid (PL) in ambient and refrigerated environments was monitored over six months. Chemical indicators (oxidation, fatty acid profile), microbiological parameters (total viable counts, yeast and moulds, Enterobacteriaceae, presumptive coliforms, Salmonella) and colour change were examined. Temperature and relative humidity of the storage environments were monitored. In the ambient …

The Physicochemical Properties Of Soy Protein Hydrolysate And Its Formulation And Stability With Encapsulated Probiotic, John Stricklin Edwards

Graduate Theses and Dissertations

Soy protein isolate (SPI) and probiotics can serve as a functional ingredient and beneficial supplement, respectively, to food formulations, but few studies focus on the compatibility of these two ingredients. The objective of this study was to prepare soy protein isolate (SPI) from defatted soybean flour and identify an optimal hydrolysis protocol to create soy protein hydrolysates (SPH) with improved solubility and functional properties and achieve an optimum encapsulation technique for probiotics and to determine the in vitro viability of encapsulated probiotic cells with SPH in a gastrointestinal environment. The SPI was prepared using an alkaline extraction procedure for solubility …

Effect Of Storage Temperature On The Survival Or Growth Of Listeria Monocytogenes On Whole And Fresh-Cut Produce, Juan F. Moreira Calix

LSU Master's Theses

Whole and fresh-cut produce are minimally processed and, therefore susceptible to microbial contamination. This study examined the survival or growth of Listeria monocytogenes on whole, and fresh-cut produce at different storage temperatures. Fresh fruits (cantaloupes, pears, pineapples, papayas, and watermelon) and vegetables (broccoli, cauliflower, lettuce, kale, and green bell peppers) were cut into 25 g pieces and were spot inoculated with 0.5 mL (8 Log CFU/mL) of Listeria monocytogenes. Inoculated fresh-cut samples were stored at 4°C or 13°C for 6 days. To represent the outer surface of the produce, cantaloupes and green bell pepper disks (20 cm2) were cut with …

Effect Of Processing On Microbiota Accessible Carbohydrates In Whole Grains, Caroline Smith

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

There is potential to increase microbiota accessible carbohydrates (MAC) in whole grains through food processing. Therefore, different processing conditions for boiling and extrusion of whole wheat flour were studied for their effect on MAC. Processing conditions had a minimal effect on fermentation response using 2 fecal samples of disparate composition. However, the processing method had an impact on the fermentation of non-digestible carbohydrates and subsequent short chain fatty acids production, but only for a microbiome with high diversity and a predominance of microbes associated with dietary fiber intake. Subsequently, five processing methods: boiling, extrusion, unleavened bread, yeast bread, and sourdough …

Prevalence And Control Of Salmonella Spp. And Sanitary Indicator Microorganisms In Wild Caught And Farm Raised Catfish (Ictalurus Punctatus), Bilan Costley Jessie

LSU Doctoral Dissertations

Catfish inspections have transitioned from the U.S. Food and Drug Administration (FDA) to the United States Department of Agriculture (USDA). The USDA Food Safety and Inspection Service (FSIS) and Food Emergency Response Network (FERN) consider it important to assess the food safety risk associated with consuming catfish in the United States. Surveillance of farm-raised and wild-caught catfish for pathogens is relevant as a public safety protocol. The purpose of this study was to detect the prevalence of Salmonella spp., identify and examine isolates for antibiotic resistance to clinical treatments, evaluate the effectiveness of antimicrobial chemical treatments against Salmonella enterica, and …

Modeling Of Free Chlorine Consumption And Escherichia Coli O157:H7 Cross-Contamination During Fresh-Cut Produce Wash Cycles, Mohammadreza Dehghan Abnavi, Ali Alradaan, Daniel Munther, Chandrasekhar R. Kothapalli, Partha Srinivasan

Mathematics and Statistics Faculty Publications

Controlling the free chlorine (FC) availability in wash water during sanitization of fresh produce enhances our ability to reduce microbial levels and prevent cross-contamination. However, maintaining an ideal concentration of FC that could prevent the risk of contamination within the wash system is still a technical challenge in the industry, indicating the need to better understand wash water chemistry dynamics. Using bench-scale experiments and modeling approaches, we developed a comprehensive mathematical model to predict the FC concentration during fresh-cut produce wash processes for different lettuce types (romaine, iceberg, green leaf, and red leaf), carrots, and green cabbage as well as …

Seaweeds As Nutraceuticals For Health And Nutrition, Emer Shannon, Nissreen Abu-Ghannam

Articles

Throughout human history, seaweeds have been used as food, folk remedies, dyes, and as mineral-rich fertilisers. Seaweeds as nutraceuticals or functional foods with dietary benefits beyond their fundamental macronutrient content are now a major research and industrial development concept. The occurrence of dietary and lifestyle related diseases, notably type 2 diabetes, obesity, cancer, and metabolic syndrome has become a health epidemic in developed countries. Global epidemiological studies have shown that countries where seaweed is consumed on a regular basis have significantly fewer instances of obesity and dietary-related disease. This review outlines recent developments in seaweed applications for human health from …

Evaluation Of Chilling Efficiency, Meat Tenderness, And Microbial Analysis Of Broiler Carcasses Using Sub-Zero Saline Solutions, Samira Viliani

Master's Theses

The poultry industry is seeking an advanced chilling system that can improve chilling efficiency, microbial safety, and water consumption without compromising meat quality. The objective of this study was to evaluate the effects of sub-zero saline chilling methods on chilling efficiency, breast fillet tenderness and microbial reduction of broiler carcasses. Following evisceration and rinsing, broiler carcasses were randomly assigned to one of three chilling solutions: 1) 0% salt or ice water control (0% NaCl/0.5^oC), 2) 3% salt (3% NaCl/-1.8^oC), and 3) 4% salt (4% NaCl/-2.41^oC) solutions. Broiler carcasses in sub-zero saline solutions reached the …

Occurrence Of Aflatoxin And Zearalenone In Concentrate Feeds And Milk Contamination With Aflatoxin M1 And Bacterial Pathogens In Malawi, Chunala Alexico Njombwa

LSU Doctoral Dissertations

Multiple studies were conducted in Malawi to: 1) evaluate knowledge and perception of dairy farmers towards molds, mycotoxins and associated adverse effects; 2) evaluate dairy farmers’ knowledge and perception on milk contamination, proper milk handling practices and adverse health effects associated with raw milk consumption; 3) determine levels of aflatoxins and zearalenone (ZEN) in concentrate feedstuffs; 4) assess prevalence and levels of aflatoxin M₁(AFM₁) in raw milk, dietary exposure and estimate HCC risks to children and adults; 5) assess Salmonella and E. colicontamination in raw and processed milk from selected small scale farms and major …

Comparison Of The Kinetic Parameters Of Escherichia Coli 0157:H7, Listeria Monocytogenes And Salmonella Typhimurium Derived From The Baranyi And Huang Models In A Chemically Defined Minimal Medium, Jose Isidro Fuentes

LSU Master's Theses

Microbial growth can be characterized by parameters such as lag time, growth rate, and maximum population density at any specific point of time. Mathematical models that predict microbial growth of foodborne pathogens are increasingly used in the food industry as a viable alternative to traditional methods of microbial enumeration. The Baranyi model has been widely used as the primary model of choice by many authors because of its performance and accuracy. The most recently developed Huang model has been less implemented and few comparisons between the Baranyi and Huang models have been made when modeling pathogenic growth. For this research, …

Understanding The Molecular Strategies Of Campylobacter Jejuni For Survival In Amoeba And Chicken., Deepti Pranay Samarth

Graduate Theses and Dissertations

Campylobacter jejuni endure to be major cause of gastroenteritis in humans worldwide. C. jejuni is fastidious in laboratory setup but can cause waterborne infection through contaminated water where none of these fastidious conditions are met. This dissertation presents an assortment of studies focused in reviewing three major factors which could present a helping hand to C. jejuni in its environmental survival viz. i) association with free-living amoebae (FLA) ii) horizontal gene transfer (HGT) contributing towards its genetic diversity iii). Viable but non-culturable (VBNC) state.

Acanthamoeba is a FLA linked to environmental survival of many intracellular pathogens, including C. jejuni. In …

Selectivity Of Infrared Heat Treatment On Inactivation Of Mycotoxigenic Fungi On Stored Grain, Shantae A. Wilson

Graduate Theses and Dissertations

Selective Infrared (IR) heating holds great potential to decontaminate spores of unsafe fungi in corn. The objectives for this study were to investigate the impact of exposing corn to infrared energy at selected peak wavelengths (λ), infrared intensities and treatment durations, followed by tempering for further inactivation of microbes on the grain and explore a method for decontaminating Aspergillus flavus (A. flavus) spores on corn. Freshly harvested corn with initial moisture contents (IMCs) of 16%, 20%, and 24% wet basis (w.b.) were used. The corn samples were treated at different infrared wavelengths (3.2, 4.5, and 5.8 μm) for 20, 40 …

Potential Antimicrobials For Controlling Listeria Monocytogenes In Frankfurters, Aaron Rashad Bodie

Graduate Theses and Dissertations

Listeria monocytogenes is a pathogenic microorganism that causes Listeriosis. Listeriosis is a highly mortal disease with approximately 20% mortality rate. Listeria is psychrophilic, therefore it is able to survive in the refrigerator. This affects foods at cool storage such as fresh produce and RTE meats. To ensure the safety of RTE meat, post processing treatments are used such as vacuum packing, edible films, dip and treatment. One-way RTE can be treated is with the use of antimicrobials. However, in the past chemical substances were used. Currently, consumers want more natural and organic preservatives to combat health problems from toxic components …

In Vitro And In Vivo (Mouse Model) Investigation Of The Efficacy Of Probiotic Bacteria Lactobacillus Casei And Lactobacillus Rhamnosus Incorporated In Tomato Juice, Bennett Atta Dzandu

LSU Doctoral Dissertations

Fruit and vegetable production in Ghana were estimated at 371,811 tons in 2017 with tomatoes ranked among the top four most cultivated vegetables. The majority of the production goes to waste due to spoilage and lack of processing. Probiotics have recently gained much attention owing to claims about their potential health benefits. However, the inability of certain probiotics to survive gastric conditions remain a potential setback. Tomatoes can be processed into value added products including those fortified with probiotics. Such value-added products can be used as protectant for the delivery of probiotics to improve gut health. The objective of this …

Sustainability Assessment Of U.S. Beef Processing And Its Antimicrobial Systems, Shaobin Li

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

With the increasing meat demand and awareness of sustainability, concerns have been raised regarding the sustainability of beef production and processing. However, scarce data and inadequate sustainability assessment frameworks for the U.S. beef processing industry limit the ability to develop new technologies and policies comprehensively without shifting sustainability burdens. To fill those gaps, various assessments of the U.S. beef processing industry were conducted from multiple perspectives regarding the environmental, economic, microbial effectiveness of its antimicrobial systems, and human health impacts from foodborne illness, occupational hazards, and environmental pollution.

First, process-level water and energy usage at a typical large-size beef processing …