Food Science Commons^™

The Elimination Of Listeria Monocytogenes Biofilms From Stainless Steel Deli Meat Slicer Components By The Use Of Hurdle Technologies, Alexandria Wynne Mertz

Graduate Theses and Dissertations

Listeria monocytogenes growth is of the greatest concern amongst ready-to-eat foods. The United States Department of Agriculture's Food Safety and Inspection Services determined that deli luncheon meats pose the greatest risk of contamination from L. monocytogenes Industrial meat slicers have many removable parts that are connected with sealers and gaskets, which can become worn over time. These spaces cannot be cleaned adequately, therefore are susceptible to bacterial growth. Planktonic cells form biofilms in order to protect the cell from adverse conditions, like during routine cleaning and sanitation. Once a biofilm is formed, the bacteria are much more difficult to eradicate …

Antibacterial Activity Of Commercially Available Plant Extracts On Selected Campylobacter Jejuni Strains, Divya Oppath Sivasankaran

Graduate Theses and Dissertations

Campylobacter jejuni is recognized as a leading cause of foodborne illness worldwide with approximately 850,000 cases per year in the United Sates. A total of 18 species of Campylobacter have been identified worldwide to date. Foodborne transmission of C. jejuni is mainly through the consumption of unpasteurized milk, contaminated poultry meat and water. C. jejuni can survive in very diverse environments under stressful conditions in human and animals which is different from the specific conditions and media required in laboratory experiments. There has been increased research in recent years to identify naturally occurring antibacterial agents to control and eliminate C. …

A Preventive Maintenance Framework In Dairy Production Operations, Maria F. Vargas

Theses and Dissertations - UTB/UTPA

Dairy operations suffer frequent stops. Product shrinkage is a consequence of downtime, which includes losses of packaging material, scraped finish product and capacity. This work proposes a troubleshooting methodology to identify causes of downtime, estimation of waste cost, and minimization of operation disruptions by applying a combination of a cost function to assess waste, and performance measurements. The drinkable yogurt process is evaluated to find the principal areas for wasted bottles and yogurt. In order to make a decision about which of those sources to address, a General Cost Function is used to estimate waste cost which include measurements that …

Development And Application Of Scalable Two-Dimensional High Performance Liquid Chromatography For Aromatic Selective Separations Of Biologically Active Phytochemicals From Oplopanax Horridus, Gregory Jones

All Dissertations

The high demand for more efficient purification processes with increased automation and throughput pushes the development of more advanced preparative, pilot, and process scale HPLC instrumentation that is capable of achieving higher purities in a shorter amount of time than are currently achieved using one dimensional separations. A preparative scale 2D HPLC system was designed and reduced to practice in order to demonstrate the capacity for scalability of on-line comprehensive 2D HPLC separations of basic compounds from a challenging natural product extract of Oplopanax horridus. The methodology and instrumentation design herein permits direct method transfer from analytical to preparative scale …

Cross-Cultural Comparison In The Emotional Responses Elicited By Wine Odors, Aimee Hasenbeck

Graduate Theses and Dissertations

To remain competitive in the wine market, wine companies must strive for a deeper understanding of the factors that influence consumers at an emotional level in order to sustain consumer satisfaction. Evaluating the wine odor-induced emotional response, in addition to hedonic response and descriptive analysis, may provide valuable information into the perspective of the consumer and potentially insight to repeat purchases. The objectives of this research were to measure the emotional responses elicited by odor attributes in wine samples and determine whether these emotional responses vary as function of cultural and experiential backgrounds, as well as sensory characteristics of wine …

Effects Of Grain Sorghum Muffin On Blood Glucose And Insulin Responses In Prediabetic Men, Xuan Gu

Graduate Theses and Dissertations

Prediabetes is a sub-health condition in the development to type 2 diabetes, which has been long overlooked. Grain sorghum contains functional starch fractions, which have been widely reported for their potential on blood glucose control and diabetes prevention. A human study with prediabetic men was conducted to investigate the effects of sorghum starch on postprandial blood glucose and insulin levels. Grain sorghum and wheat (control) muffins containing 50 g total starch were consumed by 15 prediabetic male subjects on two mornings with a 1-week washout period. Plasma samples were collected on -15 (baseline), 0, 15, 30, 45, 60, 75, 90, …

Changes In Monomeric And Polymeric Pigments During Chokeberry Juice Processing, Kail David Wilkes

Graduate Theses and Dissertations

Chokeberry consumption has been increasing due to research exposing great potential of health-promoting compounds. However, chokeberries are highly astringent and are typically consumed in processed forms in which product heating is applied. Processing chokeberries has been reported to degrade bioactive compounds, thus limiting the potential for consumers to obtain their health-promoting benefits. The purpose of this research was to examine the effects of chokeberry juice processing and storage on anthocyanin, flavonol, proanthocyanidin, hydroxycinamic acid, and polymeric pigment content, as well as percent polymeric color. In addition, new analytical methodologies were explored to better understand possible outcomes of polymeric pigments due …

Acanthamoeba Spp. As Reservoirs For Transmission Of Norovirus, Tun-Yun Hsueh

Graduate Theses and Dissertations

Human noroviruses (HuNoV) are the most common cause of foodborne disease outbreaks in the United States and the most common food commodities implicated in HuNoV outbreaks are leafy greens; however, the vehicle of transmission and point of contamination are often unknown. Here, we hypothesize that common free-living amoebae (FLA) ubiquitous in the environment may act as reservoirs of HuNoV and facilitate the transmission of these pathogens to fresh produce. The objective of this research was to first evaluate the interaction/association between HuNoV surrogates and Acanthamoeba by incubating them together and analyzing virus titer associated with amoeba through an 8 day …

Oxidative Stability Of Conjugated Linoleic Acid Rich Soy Oil Obtained By Heterogeneous Ruthenium Catalysis, Saurabh Ravindra Lele

Graduate Theses and Dissertations

Conjugated linoleic acid (CLA) has multiple health benefits but it is difficult to obtain sufficient CLA in a healthy diet to obtain the clinical effects. A CLA rich-soy oil (CLARSO) with up to 20% CLA has been produced by heterogenous catalysis but no studies of its oxidative stability have been reported. CLARSO and soy oil primary and secondary oxidation products were measured at 50oC in the dark. The CLARSO was less stable than soy oil but adsorption bleaching improved its oxidative stability. However, induction times were dependent on the analytical method used. Fatty acid oxidation kinetics was determined by measuring …

Protein Turnover In Broiler, Layers, And Broiler Breeders, Karen Vignale Lake

Graduate Theses and Dissertations

Protein turnover in skeletal tissue for broiler breeders has shown to increase at sexual maturity and then decline with increased egg production. Regarding broiler chickens the industry is facing two situations that need to be clarified: the appearance of white stripes in birds over 56 days of age and the positive effect in breast meat yield that supplementation of 25OH-D3 is causing. A series of studies were conducted to determine the effect of sexual maturity in protein turnover in broiler breeders and laying hens and to understand the effect of 25OHD3 in breast meat yield in broiler chickens and why …

Enhancement Of Antimicrobial Activity Of Naturally Occuring Phenolic Compounds By Nano-Particle Mediated Delivery Against Listeria Monocytogenes, Escherichia Coli O157:H7, And Salmonella Typhimurium, Madhuram Ravichandran

Graduate Theses and Dissertations

Food-borne illnesses are of major concern in the U.S. and worldwide. Salmonella,Listeria,E. coli O157:H7 continue to be some of the major foodborne pathogens. Recurring recalls due to these pathogens demand critical antimicrobial strategies to decontaminate the food through its procession from farm to fork. In our study, we combined the effectiveness of naturally occurring phenolic compounds individually, with/ without ethylenediamine tetraacetic acid (EDTA) and/or Nisin and nanoparticle delivery to improve the antimicrobial potential of the compounds against Listeria monocytogenes (L.m.), Salmonella Typhimurium (S.T.), and Escherichia coli O157:H7 (E.c.), in brain …

Influences Of Contexts On Consumers' Visual Attention Towards Food Images: Eye-Tracking Studies, Baoyue Zhang

Graduate Theses and Dissertations

Food perception is influenced not only by sensory properties of the food itself, but also by individuals- or environment-related contexts. Visual cue appears to be the most dominant factor in modulating food perception. This research aimed to determine whether individuals' visual attention towards food images can vary as a function of contextual variables such as hunger/fullness (Chapter 3), chronic stress (Chapter 4), and culture (Chapter 5). In Chapter 3 and Chapter 4, participants were asked to freely view visual slides, including four different images per slide, shown on the monitor. Using eye-tracking techniques, participants' visual attention towards food images (e.g., …

Effects Of Transportation Hazards On Package Performance And Food Product Shelf Life, Kyle Dunno

All Dissertations

This research studied the effect of transportation hazards on food product shelf life and package performance. Studies were conducted to determine the effect of package headspace volume, product viscosity and storage temperature on package integrity. Finally, accelerated shelf life testing (ASLT) was utilized to determine how simulated transportation hazards affected the shelf life of a specific food product. Institutional retort pouches containing either water or 5% starch solution were filled with varying amounts of headspace volume to determine if package headspace volume could aid in package performance during simulated engineering tests for packaged products. Fixed displacement vibration testing and compression …

Studies On The Initial Stage Of Lipid Oxidation In Bulk Oils, Elizabeth Budilarto

Theses

During the oxidation of bulk oils, oxidation products (i.e. peroxide values, conjugated dienes and thiobarbituric acid reactive substances) are formed gradually and increased sharply at the end of the induction period. Tocophero1s were consumed, some water was formed, and micelles increased in size during the induction period of vegetable oils oxidized in bulk. The evidence that the evolution of micellar size was in parallel with the end of induction period corroborates the recognition that micelles are the active site of oxidation. The interaction of α-tocophero1 and three synergists: ascorby1 palmitate, phosphatidy1choline and L-lysine were studied in cod liver oil, to …

Fearless Friday: Sean Pethybridge, Christina L. Bassler

SURGE

Talking with Sean Pethybridge ’15, one could easily assume his interest in agriculture and food justice developed at a very young age. Sean confesses that he had very limited knowledge prior to attending Gettysburg. “My grandpa had a garden and the most experience I had with that was picking green beans during the summer time when I was younger,” he jokes. [excerpt]

Freeze Dried Blueberry Powder Fortification Improves The Quality Of Gluten Free Snacks, Sikha Bhaduri, Khursheed Navder

Publications and Research

Since Quinoa flour is an excellent source of natural antioxidant compounds and blueberries are rich in polyphenolic anthocyanins, this study was undertaken to improve and evaluate the quality of two blueberry powder fortified gluten free products, muffins and cookies. Control products were made with 100% Rice flour and Rice flour was replaced by 50% and 100% Quinoa flour to prepare muffin and cookies. 10% freeze dried Blueberry powder was used for fortification. Effect of flour replacements and Blueberry fortification on moisture content, water activity, antioxidant value, shelf life, sensory quality and textural properties were studied. Blueberry fortification improved the shelf …

Effect Of Plasticizer On Oxygen Permeability Of Cast Polylactic Acid (Pla) Films Determined Using Dynamic Accumulation Method, Kurniawan Yuniarto, Bruce A. Welt, Aris Purwanto, Hadi Karia Purwadaria, Ayman Abdellatief, Titi C. Sunarti, Setyo Purwanto

Journal of Applied Packaging Research

Polylactic acid (PLA) is becoming an increasingly important biopolymer for packaging applications. PLA brittleness limits its applicability. This study evaluated PLA properties with increasing amounts of added polyethylene glycol (PEG) plasticizer. Oxygen transmission rate (OTR) of cast films was determined using the newly available Dynamic Accumulation (DA) method. Arrhenius temperature sensitivity of OTR and polymer Permeability was also determined. Permeability of neat PLA is 4.848 ml mm (STP)/m² s kPa; hence, 4.84 ml mm (STP)/m² s kPa, 4.07 ml mm (STP)/m² s kPa and 5.42 ml mm (STP)/m² s kPa by adding PEG 1 %, 5% …

Development Of A Methodology To Measure The Effect Of Ergot Alkaloids On Forestomach Motility Using Real-Time Wireless Telemetry, Amanda M. Egert, James L. Klotz, Kyle R. Mcleod, David L. Harmon

Animal and Food Sciences Faculty Publications

The objectives of these experiments were to characterize rumen motility patterns of cattle fed once daily using a real-time wireless telemetry system, determine when to measure rumen motility with this system, and determine the effect of ruminal dosing of ergot alkaloids on rumen motility. Ruminally cannulated Holstein steers (n = 8) were fed a basal diet of alfalfa cubes once daily. Rumen motility was measured by monitoring real-time pressure changes within the rumen using wireless telemetry and pressure transducers. Experiment 1 consisted of three 24-h rumen pressure collections beginning immediately after feeding. Data were recorded, stored, and analyzed using …

Dietary Carbohydrates Influence The Structure And Function Of The Intestinal Alpha-Glucosidases, Mohammad Chegeni

Open Access Dissertations

As the primary products of starch digestion by pancreatic α-amylase, maltooligosaccharides (including maltose) are the main substrates for the α-glucosidases at the intestinal brush border. Here, maltose was shown to induce the formation of a higher molecular weight (HMW) sucrase-isomaltase (SI) species in Caco-2 cells that sorts more quickly to the enterocyte surface to act as a digestive enzyme. As this finding suggested a maltose sensing ability of small intestinal enterocytes, molecular mechanisms associated with the maturation and trafficking of HMW SI were further investigated. A pulse-chase experiment using [ ³⁵S]-methionine revealed a higher rate of early trafficking and …

Quality And Safety Attributes Of Sun-Dried Raisins From Afghanistan, Stacy A. Mccoy

Open Access Theses

Raisins are an important export commodity for Afghanistan, however, Afghan packers are challenged to export to markets seeking high quality products due to limited knowledge regarding their quality and safety. To evaluate this, Afghan raisin samples from pre-, semi-, and post-processed raisins were obtained from a raisin packer in Kabul, Afghanistan. The raisins were analyzed and compared to U.S. standards for processed raisins. The samples tested did not meet U.S. import standards for embedded sand, but the process used to clean the raisins is suitable to maintain food safety standards.

Previous Afghan raisin shipments have been rejected from the U.S. …