Food Microbiology Commons^™

Aqueous Ozone Efficacy For Inactivation Of Foodborne Pathogens On Vegetables Used In Raw Meat-Based Diets For Companion Animals, Sahaana Chandran, Christopher A. Baker, Allyson N. Hamilton, Gayatri R. Dhulappanavar, Sarah L. Jones, Kristen E. Gibson

Food Science Faculty Publications and Presentations

The present study evaluates the efficacy of a batch wash ozone sanitation system (BWOSS) and spray wash ozone sanitation system (SWOSS) against Listeria monocytogenes (two strains) and Salmonella enterica subsp. enterica (three serovars) inoculated on the surface of carrots, sweet potatoes, and butternut squash, commonly used in raw meat-based diets (RMBDs) marketed for companion animals such as dogs and cats. Produce either remained at room temperature for 2 h or were frozen at −20°C and then tempered overnight at 4°C to mimic the preprocessing steps of a raw pet food processing operation (‘freeze-temper’) prior to ozone treatment. Two ozone concentrations …

Kluyveromyces Marxianus Prepared As A Ready To Use Supplemental Food (Rusf), Zachary Christman

Applied Science Program: Theses

Ready to Use Supplemental Food (RUSF) is a nutrient dense paste or compressed bar used to supplement a person’s nutritional needs because of malnutrition or due to food shortages. The purpose of this article is to demonstrate some methods of how the dairy organism Kluyveromyces marxianus can be used to enrich the protein value of bread or ferment a substrate such as wheat bran into a more digestible form.

Persistence Of Salmonella Enterica Subsp. Enterica Ser. Javiana, Listeria Monocytogenes, And Listeria Innocua In Hydroponic Nutrient Solution, Gayatri R. Dhulappanavar, Kristen E. Gibson

Food Science Faculty Publications and Presentations

This study aimed to determine the persistence of Salmonella Javiana, Listeria monocytogenes, and Listeria innocua in nonsterile, hydroponic nutrient solution (NS) at 15, 25, 30, and 37°C over a 21-day period to mimic time from seedling to mature lettuce. Bacteria were inoculated in modified Hoagland's NS at 106 CFU/mL and maintained at 15, 25, 30, and 37°C. Samples were collected at various time points, and bacteria were quantified. A mixed model was used to determine the effect of bacteria type, time (day), and temperature on bacteria concentration (log CFU/mL). The least-squares means were calculated to compare the mean log …

Influence Of Overcooking On Food Digestibility And In Vitro Fermentation, Wensheng Ding

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

Areas of char or overcooking commonly appear in foods people consume. It has been reported that overcooked food is harmful to human health. However, little research exists on the effect of overcooking on in vitro protein and starch digestibility and gut microbial fermentation. This study aimed to reveal the connection between overcooking and in vitro protein and starch digestibility and gut microbial fermentation. In vitro protein digestibility of an overcooked ground beef patty was almost half that of a standard cooked sample (27 ± 2% versus 48 ± 6%, respectively; p = 0.02). Whole wheat bread protein digestibility was also …

Effect Of Authentic Kefir And Nigella Sativa On Broilers Challenged By Coccidia And Clostridium Perfringens, Julian E. Nixon

All Dissertations

Black seed oil concentrations of 0%, 0.1%, 1% and 5% were added to milk inoculated with kefir grains and incubated at 25°C for 22 h. The pH and microbial count indicated 1% black seed oil caused low inhibition (P > 0.05) of fermentation, but 5% black seed oil caused significant inhibition of the kefir microorganisms (P < 0.05).

Cobb 500 male chicks (n = 256) were distributed in a randomized block design and received one of four treatments: CTRL1 (Non-medicated, no kefir, no Clostridium perfringens), CTRL2 (Non-medicated, no kefir, C. perfringens inoculated), CTRL3 (BMD medicated, no kefir, C. perfringens inoculated), KTRT (Non-medicated, …

Nutritional Characteristics, Microbial Loads And Consumer Acceptability Of Cookies Enriched With Insect (Ruspolia Differens) Meal, Brian O. Ochieng, Joseph O. Anyango, Fathiya M. Khamis, Sunday Ekesi, James Peter Egonyu, Sevgan Subramanian, John M. Nduko, Dorothy Nakimbugwe, Xavier Cheseto, Chrysantus M. Tanga

All Peer-Reviewed Publications

Utilization of Ruspolia differens Serville as functional food ingredient is rapidly gaining popularity. This study evaluated the nutrient quality, microbial safety and consumers’ acceptability of cereal-based cookies fortified with various processed products of R. differens meals. Cookies fortified with blanched, boiled, and toasted R. differens meals had higher protein, fat and energy levels, respectively, than the control cookies. Enrichment of cookies with differentially processed R. differens meals had elevated levels of isoleucine and leucine. Omega-3 fatty acid, methyl (9Z,12Z,15Z)-octadecatrienoate, was detected only in cookies prepared from wheat-insect meals blends. Blanched and boiled R. differens meal significantly (p < 0.05) boosted iron (1.70-folds) and zinc (1.12–1.16-folds) contents of the cookies. The cookie products had reduced Enterobacteriaceae, S. aureus, yeast and mould with permissible exposure limits for human consumption. The overall acceptability of insect-enriched cookie product by male and female respondents ranged between 57 and 80%. The survey revealed that the flavour, colour, mouthfeels and texture of the cookie products were important motivation for consumers to accept grasshoppers as a food source. Further research on the flavour of cookie products enriched with grasshopper meal would be required to increase acceptability to market-driven consumer appealing food products.

Evaluating Salmonella Cross Contamination In Raw Chicken Thighs In Simulated Post-Chill Tanks, Raziya Sadat

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

Salmonella contamination poses a significant risk to food safety, particularly in poultry products and public health. This study aims to investigate the effectiveness of peracetic acid (PAA) treatment in mitigating Salmonella cross-contamination in chicken thighs within simulated post-chill tanks, considering different inoculum concentrations and organic matter (OM) levels.

The experiment involved the use of five distinct Salmonella serovars to inoculate chicken thighs, which were categorized into two groups: higher inoculation level (ca. 7 log CFU/mL) and lower inoculation level (ca, 4 log CFU/mL). These groups underwent treatment with four different solutions, including 540 ppm PAA with 1.5% OM, 540 ppm …

Linking The Metabolic And Ecological Fate Of Caribbean Ciguatoxins And Related Neurotoxins In Reef Herbivores, Jessica K. Gwinn

Graduate Theses and Dissertations (2019 - present)

Ciguatera poisoning (CP) is one of the most prominent seafood-borne illnesses worldwide, affecting between 25,000–500,000 people annually. Ciguatera is caused by the ingestion of seafood contaminated with algal-derived ciguatoxins (CTX), the precursors of which are produced by benthic and toxigenic dinoflagellates in the genera Gambierdiscus and Fukuyoa. These compounds enter marine food webs through herbivory and are subsequently transferred to higher trophic levels, undergoing complex metabolic biotransformations, which produce structurally related CTX derivatives. Consumption of CTX induces a variety of severe neurological, gastrointestinal, and/or cardiovascular symptoms beginning within hours and lasting for weeks to months following exposure. Despite the impact …

Characteristics Of Yogurt And Culture Bacteria As Affected By Ingredients That Help Treat Leaky Gut, Ricardo Jose Santos Aleman

LSU Doctoral Dissertations

At least 100 million people have leaky gut syndrome. This syndrome is associated with multiple health problems such as diabetes, celiac disease, asthma, multiple sclerosis, and inflammatory bowel disease, costing more than $3 billion per year to treat. L-Glutamine, quercetin, slippery elm bark, marshmallow root, N-acetyl-d-glucosamine (NAG), licorice root, maitake mushrooms, and zinc orotate have been reported to help treat leaky gut.

The objectives were to explore the characteristics of yogurt and culture bacteria as affected by ingredients that help treat leaky gut. In yogurt, the pH, titratable acidity, syneresis, viscosity, color, Streptococcus thermophilus, Lactobacillus bulgaricus, yeast and mold and …

Enhancing Lovastatin Biosynthesis In Oyster Mushrooms (Pleurotus Ostreatus) Using Phytohormones, Fransisca Astrid Mustafa, Mamat Kandar, I Nyoman Pugeg Aryantha

Makara Journal of Science

The biosynthesis of lovastatin, the anti-cholesterol compound, in oyster mushrooms (Pleurotus ostreatus), has the potential to be enhanced by utilizing phytohormones, which activate the expression of certain genes. This research aimed to determine the best type and concentration of phytohormone among auxin, gibberellin, and cytokinin, as well as the best mycelial colonization percentage in F2 medium to realize the greatest increase in lovastatin biosynthesis in oyster mushrooms. Lovastatin was extracted from the fruiting bodies and mycelia and analyzed by spectrophotometry. The analysis of CYP450 linked to lovastatin biosynthesis was conducted by quantitative polymerase chain reaction (qPCR) using samples containing …

Microbiological Safety And Quality Of Ceviche, Poke, And Sushi Dishes Sold At Retail Outlets In Orange County, Ca, Grace E. Marquis, Samantha M. Covaia, Amanda M. Tabb, Courtney J. Kitch, Rosalee S. Hellberg

Food Science Faculty Articles and Research

Raw, ready-to-eat (RTE) seafood products, such as ceviche, poke, and sushi, have experienced growing demand globally; however, these products have the potential to be contaminated with foodborne pathogens. The objective of this study was to determine the prevalence of Escherichiacoli/coliforms, Salmonella, and Listeria in ceviche, poke, and sushi dishes sold at the retail level in Orange County, CA, USA. Additional organisms detected during testing were also considered in the results. A total of 105 raw, RTE samples of ceviche, poke, and sushi were collected from restaurants and grocery stores in Orange County, CA. Samples were tested for Salmonella …

Evaluation Of Potential Surrogates For Listeria Monocytogenes In Fresh Citrus-Specific Validation Studies, Kimiko Grace Casuga

Master's Theses

The FSMA Produce Safety Rule (PSR) requires citrus packers to more closely assess, manage, and monitor food safety risks. Although there have been no foodborne illness outbreaks and only one recall in fresh citrus, the risk of pathogens coming in on the fruit and cross contamination during washing still exists. Packhouses have dynamic washing systems and in-plant validations may be the only way to demonstrate compliance with the PSR. In-plant validations use surrogates in place of pathogens, and none have been identified or validated for citrus. The aim of this research was to identify a surrogate for use in fresh …

Determining The Effects Of Maternal Adiposity On Preterm Neonatal Microbiome And Short Chain Fatty Acid Profiles, Dalton James, William A. Clark Phd, Kristy L. Thomas

Undergraduate Honors Theses

The gut microbiota and its metabolites have vast impacts on the human digestive system, immune system, and health outcomes. Short chain volatile fatty acids (SCVFAs) present in feces can be representative of the interactions of the microbiota present in the gut. Low microbiota diversity in the human gut is highly associated with obesity and adverse health outcomes. Furthermore, the maternal microbiome has a direct impact on neonatal microbiota through various pathways such as environment, skin flora, breast milk composition, and vaginal secretions. This study is aimed to further understand the associations between various factors (maternal adiposity, gestational time, length of …

Single-Laboratory Validation For The Detection Of Salmonella Enterica In Meat Analog Products, Amanda Tabb

Food Science (MS) Theses

Meat analogs are becoming increasingly popular for health, environmental, and ethical reasons. However, these products are at risk for contamination with Salmonella enterica. Therefore, it is important to ensure that detection methods for S. enterica in meat analog products are effective. Currently, the Bacteriological Analytical Manual (BAM) chapter on Salmonella detection calls for pre-enrichment of meat analogs using lactose broth (LB) with added surfactants, Tergitol Anionic 7 or Triton X-100. However, it remains to be determined whether surfactants are necessary for pre-enrichment of meat analogs. Following pre-enrichment, screening with VIDAS is typically performed. While VIDAS is an effective screening method, …

Optimizing Soil Nutrient Management To Improve Dry Edible Bean Yield And Protein Quality, Emily Jundt

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

Soil nutrient management is of the utmost importance to ensure crop yields are maximized to feed the world’s growing population. Micro and macronutrient deficiencies can be detrimental to plant growth and cause a drastic reduction in yield. Optimization of nutrient management needs extensive research. Nutrients such as nitrogen increase crop yield, even in legumes capable of using a large amount of nitrogen (N) via biological N fixation. Iron (Fe) fertilizers are also crucial for legumes as they are susceptible to Fe deficiency induced chlorosis.

Dry edible beans (Phaseolus vulgaris) are leguminous plants and excellent dietary protein sources. Great …

Inhibiting Survival Of Salmonella During Desiccation Through The Use Of Naturally Occurring Signals, Joseph Headrick

Electronic Theses and Dissertations

A rising problem in agriculture is the increase of antibiotic-resistant Salmonella cases associated with chicken eggs, which transmit infection to humans. To counter this, new approaches to combat Salmonella in chickens and desiccated on eggshells are vital in the prevention of human foodborne illness. Disrupting signaling pathways with naturally occurring compounds provides a potential novel avenue for prevention of Salmonella infections, as this would disrupt sensing of these environments and inhibit subsequent optimal gene expression. Starting with signals identified in previous studies, salicylic acid was found to inhibit Salmonella desiccation survival on both eggshells and plastic. To expand upon this, …

Filth Flies As A Vector For Some Pathogenic Bacteria Transfer, Ahmet Buyukyavuz

All Dissertations

Two separate sets of experiments were conducted to determine the transfer of bacteria by flies. An Escherichia coli ampicillin-resistant strain with a fluorescent gene was used during the experiments. The first set of experiments were divided into two trials to measure the transfer of E. coli by fruit flies to apple slices and bologna during short term exposure. Short time exposure (1, 5 and 15 min) of flies to inoculated apple slices were tested in the first trial to determine the transfer of E. coli to flies. No difference (P>0.05) in the number of bacteria transferred to flies were …

The Science Of Baking Bread, Admin Stem For Success

STEM for Success Showcase

Activity plan to teach biology and chemistry using a lesson on the baking of bread.

Fusarium Species Structure In Nebraska Corn, Yuchu Ma

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

Fusarium species are known to infect corn and cause significant yield losses and mycotoxin contamination worldwide. In this study, we investigated the diversity of Fusarium species infecting corn in Nebraska and their potential to produce fumonisins and trichothecenes. A total of 259 Fusarium isolates were collected from different corn tissues (ear, stalk, and root), revealing a significant association between the various Fusarium species complexes and different plant parts (p < 0.05). Fusarium incarnatum-equiseti species complex (FIESC) was the most widespread and abundant, followed by the Fusarium sambucinum (FSAMSC) and Fusarium fujikuroi species complexes (FFSC). In the subsequent analysis, we investigated the mycotoxin …

Development Of Value-Added Butter By Incorporating Whey Protein Hydrolysate-Encapsulated Probiotics, Kritika Gaba, Sanjeev Anand, Athira Syamala

Dairy Science and Food Science Faculty Publications: 2022 to Present

The probiotic foods market is growing exponentially; however, probiotics’ survivability and interaction with product attributes pose major challenges. A previous study of our lab developed a spray-dried encapsulant utilizing whey protein hydrolysate-maltodextrin and probiotics with high viable counts and enhanced bioactive properties. Viscous products such as butter could be suitable carriers for such encapsulated probiotics. The objective of the current study was to standardize this encapsulant in salted and unsalted butter, followed by storage stability studies at 4 ◦C. Butter was prepared at a lab-scale level, and the encapsulant was added at 0.1% and 1%, followed by physiochemical and microbiological …