Food Microbiology Commons^™

Inactivation Kinetics Of Escherichia Coli And Listeria Monocytogenes In Edible Insects, Precious Aduloju

Graduate Theses, Dissertations, and Problem Reports (ETD)

Edible insects are emerging as sustainable and nutritious alternatives to conventional protein sources. However, concerns about food safety, particularly the presence of pathogenic bacteria such as Escherichia coli and Listeria monocytogenes, remain a barrier to consumer acceptance and industrial use. This study evaluated the effectiveness of thermal processing in inactivating E. coli, L. monocytogenes, and their non-pathogenic surrogates (E. coli JM109 and Listeria innocua) in both fresh and dehydrated forms of Tenebrio molitor (mealworm) and Acheta domesticus (cricket). It also evaluated the influence of insect species, moisture content, and temperature on microbial inactivation. A microbial challenge …

Comparative Evaluation Of Fungal Strains For The Bioprocessing Of Soybean Hulls Using Cheese Whey As Fermentation Medium, Ruchita Bhattarai

Electronic Theses and Dissertations

Globally, soybean is the most widely cultivated oilseed crops, and serve as the primary source of cooking oil, contributing to around 50% of global oilseed production. During the industrial processing of soybean oil, a significant amount of soybean hull (SH) is produced, which makes up about 8% of the grain yield, resulting in approximately 18–20 million tons of hulls, one of the largest by-products in the soybean industry. The hulls have limited commercial value and are primarily used as fiber additives in dairy cattle feed, but a large portion is still discarded as agricultural waste. Similarly, cheese whey (CW), a …

Science, Physiology, And Nutrition For The Nonscientist, Judi S. Morrill

Open Educational Resources

A wonderful blend of physiology, nutrition, biochemistry, genetics, biology, evolution, chemistry--what we all need to know as informed citizens. A basic knowledge of the life sciences and how our bodies work--to promote our own good health, especially as we're bombarded with misleading advertisements, soundbites, and the like. DNA fingerprinting, calorie requirements, dietary advice, genetic engineering (including gene editing with CRISPR cas9)--all in an easy-to understand book.

Aflatoxin Prevalence And Association With Maize Grain Physical And Nutritional Qualities In The Informal Markets In Meru County, Kenya, C. Cherotich, M. W. Okoth, Abong’ Go, S. W. Kariuki, E. R. Omuse

All Peer-Reviewed Publications

In Kenya, aflatoxin contamination in maize remains a persistent issue, with potential negative impacts on both public health and economic growth. Aflatoxins are toxic secondary metabolites produced by certain mold species, primarily Aspergillus flavus. The extent of Aspergillus fungal invasion in maize grains and the resulting increase in aflatoxin levels is heavily influenced by pre-and post-harvest practices. Before harvest, factors such as insect damage and exposure to warm, humid conditions increase the crop's susceptibility to Aspergillus infection and subsequent aflatoxin formation. Post-harvest, additional risks arise when kernels are damaged by pests like rats or when they are stored in unfavorable …

Processed Amaranth And Finger Millet Enriched With Cricket Flour Influence The Functionality, Microbial Quality, Shelf Life, And Consumer Preference Of The Porridge Products, Nelly Maiyo, Michael Okoth, George Abong, Brian O. Ochieng, Fathiya Khamis, Margaret Kababu, Chrysantus M. Tanga

All Peer-Reviewed Publications

Exploration of nutritious, cheap, and easy-to-prepare locally available complementary foods using different processing techniques is gaining traction globally. This study evaluated the impact of three processing techniques (roasting, germination, and fermentation) on finger millet and amaranth quality. The implications of blending processed products with 10% cricket flour on the functional properties, microbial safety, and shelf life of the porridge products were tested. Thereafter, consumer preference and acceptability of the cooked porridge products were assessed with randomly enrolled panelist of mothers (20–66 years), as primary caregivers. Our results showed that powder from germinated cereal products had higher swelling power, water absorption …

Using Bivalves As An Indicator For Fecal Bacteria, Kamala Chuss

Honors Scholar Theses

This project focuses on the integration of fecal bacteria from warm-blooded animals into bivalve tissue, and the utilization of bivalves as an indicator for fecal bacteria in waterways. Bivalves may give a more representative long-term average of fecal bacteria in water as compared to direct water testing. The primary objective is to create a standard operating procedure to use bacterial testing of bivalves as a proxy for bacteria concentration in the water. This method can be used in places where bivalves do not already exist by adding them to a body of water, or by collecting bivalves that already exist …

Development Of Fortified Blended Food Using Great Northern Bean, Aemiro Tadesse Zula

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

Undernutrition is a global health challenge affecting people across all stages of life. While everyone is susceptible, certain groups face a significant burden. These include those living in poverty, young children, adolescents, older people, and lactating and pregnant women. Food insecurity is another primary global concern affecting billions of individuals worldwide and is closely associated with undernutrition. Implementing interventions to address these two significant global burdens is critical, and international organizations are playing a crucial role through food aid programs using Fortified Blended Foods such as corn-soy blend (CSB), corn-soy blend plus (CSB+), and corn-soy blend plus plus (CSB++). CSB+ …

Effects Of Heat Moisture Treatment On Dietary Fiber Utilization By The Gut Microbiota, Yichen Bai

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

The present study investigates the impact of heat moisture treatment (HMT) on the utilization of dietary fibers from red lentil hulls and wheat bran and its subsequent effect on gut microbiota and short-chain fatty acid production. HMT significantly decreased the water absorption index in red lentil hulls but increased it in wheat bran. For resistant starch (RS), HMT elevated its content in red lentil hulls but diminished it in wheat bran. In terms of dietary fiber content, HMT increased soluble dietary fiber in red lentil hulls. However, carbohydrate utilization and SCFA production by gut microbiota did not significantly change after …

Multidrug-Resistant Esbl-Producing Escherichia Coli Coexisting With Colistin-Resistance Genes In Pig Farms, Central Thailand, Wipawee Songsaeng, Nutthee Am-In, Nuvee Prapasarakul, Wandee Sirichokchatchawan

The Thai Journal of Veterinary Medicine

The presence of extended-spectrum beta-lactamase and colistin resistance E. coli in food-producing animals is a public health concern. This study was conducted using a rigorous methodology to survey the prevalence of ESBL-producing and colistin-resistant E. coli from pig farms in the central part of Thailand. A total of 519 samples were collected from fecal, feed, and waste in 53 farms located in central Thailand. All samples were inoculated onto selective agar, and species identification was performed using biochemical assays and MAlDI-TOF MS. Antimicrobial susceptibility was determined by broth microdilution, and ESBL production was confirmed by the combination disc diffusion method. …

Microbial Transfer And Cross-Contamination In Milling Facilities And Pathogen Survival In Milled Products And Baking Mixes, Aryany Leticia Peña-Gomez

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

Wheat-based products, traditionally considered low-risk due to their low moisture content, have been involved in numerous foodborne outbreaks in recent decades. Salmonella and Shiga toxin-producing Escherichia coli (STEC) present in these products have caused significant numbers of hospitalizations and massive product recalls. The microbiological quality of flour is highly dependent on the incoming wheat, which is vulnerable to contamination from field to milling. Once pathogens are present in flour, they can survive for extended periods. Implementing strategies to mitigate the risk of pathogen contamination throughout the wheat processing chain is critical.

This study evaluated the distribution of E. coli …

Development And Validation Of Aronia Melanocarpa Berry Recipes For Home Canning: Integrating Thermal Lethality Studies, Microbiological Safety, And Antioxidant Analysis, Juan Diego Villegas Posada

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

Aronia melanocarpa, also known as chokeberry, is gaining popularity for its high antioxidant content and health benefits, including reducing oxidative stress and inhibiting cancer gene expression. However, its characteristic bitterness and astringency limit its broader appeal. Chokeberry's low pH places it in the acid foods category, making it ideal for safe home canning. An acidic environment combined with heat treatment inhibits harmful bacteria like Clostridium botulinum. Home canning preserves food by sealing it in airtight containers and heating it to destroy spoilage microorganisms.

Developing safe and palatable recipes is essential for making chokeberries suitable for home canning. A …

The Effect Of Fat Content On The Inactivation And Recovery Of Listeria Spp. In Ready-To-Eat Foods After High Pressure Processing, Yhuliana Kattalina Niño Fuerte

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

High-pressure processing (HPP) is recognized by the United States Department of Agriculture Food Safety and Inspection Service (USDA FSIS) as a post-lethality treatment to control Listeria monocytogenes in ready-to-eat (RTE) meat and poultry products. A scoping review of 603 journal articles, which ultimately was narrowed down to 16 articles, revealed that the efficacy of HPP varies with fat content. The studies demonstrated that L. monocytogenes inactivation by HPP tends to be lower in RTE meats with greater than 5% fat content, compared to products with lower than 5% fat. The wide range of HPP parameters used in these studies …

Interactions Between High-Pressure Processing And Natural Antimicrobials In Ground White-Meat Chicken: An Analysis Of Microbial, Textural Charactheristics And Physicochemical Changes, Amalia M. Diaz Alejandro

All Theses

High Pressure processing is an innovative technique for preserving a wide variety of foods, including meat, and this method is increasingly used to satisfy consumer demand for quality food products. High-pressure treatment can impact, negatively or positively, various aspects of meat quality, including color, texture, protein denaturation, and microbial stability, particularly when food products are processed at ambient or low temperatures. By minimizing thermal exposure, appropriate high-pressure ranges help to prevent quality and nutrition degradation, reduce microbial contamination, and enhance tenderness.

The first objective of this research was to examine the influence of high-pressure processing and addition of natural antimicrobials …

Twenty-Three Years Of Pcr-Based Seafood Authentication Assay Development: What Have We Learned?, Maleeka Singh, Robert G. Young, Rosalee S. Hellberg, Robert H. Hanner, Maria G. Corradini, Jeffrey M. Farber

Food Science Faculty Articles and Research

Seafood is a prime target for fraudulent activities due to the complexity of its supply chain, high demand, and difficult discrimination among species once morphological characteristics are removed. Instances of seafood fraud are expected to increase due to growing demand. This manuscript reviews the application of DNA-based methods for commercial fish authentication and identification from 2000 to 2023. It explores (1) the most common types of commercial fish used in assay development, (2) the type of method used, (3) the gene region most often targeted, (4) provides a case study of currently published assays or primer-probe pairs used for DNA …

Utilization Of Probiotics To Compete With Clostridioides Difficile For Nutrient-Niches In A Variety Of In Vitro Contexts, April Elizabeth Johnson

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

Clostridium difficile is a major threat to public health and primarily affects at risk groups such as elderly, immunocompromised individuals, and individuals on antibiotics. Many decades of research have been conducted to figure out ways to exclude or reduce C. difficile colonization and toxin production. Two major proposed mechanisms for colonization resistance are production of secondary bile salts and competition for nutrients.

In Chapter 2, we found that antibiotic treatment disrupted bile salt metabolism increasing the levels of the primary bile salt cholate and decreasing the levels of deoxycholate, a secondary bile salt. However, bile salts were not required …

Assessment Of Foam Decontamination In Tomato Washing Process, Basim M. Alohali

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The work of the dissertation investigated the efficacy of foam-based decontamination treatments to enhance microbial safety in Roma tomatoes, specifically targeting natural microflora and Salmonella contamination. Growing concerns over foodborne illnesses linked to fresh tomatoes and the limitations of conventional decontamination techniques, such as organic matter built-up and limited microbial reduction, are addressed. The primary objectives were to characterize the physiochemical properties of foams formed using various concentrations of Tween 20 (T20) and sodium dodecyl sulfate (SDS) with and without the addition of sodium hypochlorite (NaOCl) and peracetic acid (PAA), compare the efficacy of foam and traditional dump tank (DT) …

Microbiological And Physicochemical Changes In Rabbit Meat During Ambient Storage, Marielle Gamboa, Dennis Marvin Santiago, April Shayne Sulabo, Mary Ann Torio

The Philippine Agricultural Scientist

This study aimed to evaluate the changes in rabbit meat during storage at ambient temperature (30 ± 1ºC) for nine hours. The study focused on two rabbit muscle parts: the hind leg and the saddle, investigated in terms of microbiological parameters such as aerobic plate count (APC) and total coliform count (TCC); and physicochemical parameters such as pH, color, total myoglobin concentration, and lipid oxidation. Data obtained were subjected to statistical analysis at a 5% significance level (p < 0.05). Results revealed that the pH of both portions of rabbit muscle decreases over time during storage. This decrease is attributed to the growth of acid-producing microorganisms, which ultimately leads to spoilage in rabbit meat. On the contrary, color values (L*, a*, and b*) showed an increasing trend in both muscle portions, indicating a discoloration of rabbit meat during storage. Both lipid oxidation and total myoglobin content of rabbit meat did not change significantly during storage, but lipid oxidation varied between muscle parts. Based on the microbiological analysis of rabbit meat, both aerobic plate count (APC) and total coliform count (TCC) increased significantly during storage in both muscle portions. Results of the study suggest that freshly slaughtered rabbit meat must remain at ambient storage for the shortest time, as this storage condition will cause spoilage of meat, making it unfit for human consumption.

College Students’ Domestic Kitchen Food Safety Perceptions And Knowledge, Kailing Chen, Zhihong Lin, Isabelle Do Prado, Zahra Mohammad, Karla M. Acosta, Sujata A. Sirsat

Journal of Extension

This study investigates college students’ current food safety knowledge and food-handling perceptions and utilized an online survey which designed based on previous studies as method. The questionnaire measured respondents’ food safety knowledge and perception, and were divided into knowledge, attitudes and perception categories. The results show that college students significantly lacked in basic food safety knowledge as well as food handling skills and implies a high need to develop enhanced food safety resources for college students, especially on topics related to cross-contamination prevention, correct food preparation procedures, time and temperature control, and awareness of pathogens that cause foodborne illness.

Protein Oxidation In Aging And Alzheimer’S Disease Brain, Rukhsana Sultana, D. Allan Butterfield

Markey Cancer Center Faculty Publications

Proteins are essential molecules that play crucial roles in maintaining cellular homeostasis and carrying out biological functions such as catalyzing biochemical reactions, structural proteins, immune response, etc. However, proteins also are highly susceptible to damage by reactive oxygen species (ROS) and reactive nitrogen species (RNS). In this review, we summarize the role of protein oxidation in normal aging and Alzheimer’s disease (AD). The major emphasis of this review article is on the carbonylation and nitration of proteins in AD and mild cognitive impairment (MCI). The oxidatively modified proteins showed a strong correlation with the reported changes in brain structure, carbohydrate …

Lmpact Of Salmonella Enterica Effector Proteins On Plant Physiology And Immunity, Sara Qader

Honors Theses

Salmonella enterica serovar Typhimurium are primarily recognized as pathogens associated with foodborne illnesses in humans. Salmonella also can colonize plant tissue effectively. The pathogen relies on type III secretion systems (T3SS) to infect mammals and plants successfully and counteract the immune response. Understanding the molecular mechanisms underlying Salmonella’s interactions with plants is essential for developing effective strategies to reduce its impact on human health and agriculture. Effector proteins, known for their role in modulating host-pathogen interactions, have been implicated in the virulence and pathogenicity of Salmonella. However, their specific functions and contributions to Salmonella’s interactions with plants remain largely unknown. …