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Comparison Of Methods For Detection Of Listeria On Wooden Shelves Used For Cheese Aging: Challenges Associated With Sampling Porous Surfaces, Gina Christine Frontino Jan 2019

Comparison Of Methods For Detection Of Listeria On Wooden Shelves Used For Cheese Aging: Challenges Associated With Sampling Porous Surfaces, Gina Christine Frontino

Graduate College Dissertations and Theses

This thesis examined the efficacy of various sampling and detection methods used for environmental monitoring of Listeria species on wooden surfaces used for cheese aging. Government agencies including the Food and Drug Administration (FDA) and United States Department of Agriculture (USDA) recommend enrichment methods coupled with use of environmental sponges and swabs. Our study compared efficacy of sponge swabs manufactured by 3M™ and World Bioproducts. There is a lack of research validating the best performing swab type and enrichment method combination that is sensitive when used on rough, porous surfaces. The sensitivity of these environmental sampling tools and methods are ...


An Environmental Approach To Food Safety Assessment Using Artisan Cheese And Fresh Produce As Model Systems, Marie Limoges Jan 2019

An Environmental Approach To Food Safety Assessment Using Artisan Cheese And Fresh Produce As Model Systems, Marie Limoges

Graduate College Dissertations and Theses

This dissertation examined recently issued regulatory standards using cheese and produce as model systems. FDA's 2015 Domestic and Imported Cheese and Cheese Products Compliance Program Guidelines (CPG) E. coli standards on cheese safety, and the extent to which these standards affect domestic and imported cheese commerce, was assessed. Results from FDA's Domestic and Imported Cheese Compliance Program for samples collected between January 1, 2004 and December 31, 2006 were analyzed. Of 3,007 cheese samples tested for non-toxigenic E. coli, 76% (2,300) of samples exceeded 10/g, FDA's target for regulatory activity. In cheese samples containing ...


Analysis Of Surface Crystals On Soft Washed Rind Cheeses Using Polarized Light Microscopy And Their Effect On The Sensory Perception Of Grittiness, Patrick Polowsky Jan 2018

Analysis Of Surface Crystals On Soft Washed Rind Cheeses Using Polarized Light Microscopy And Their Effect On The Sensory Perception Of Grittiness, Patrick Polowsky

Graduate College Dissertations and Theses

With the rising popularity of artisanal cheese in the United States, the soft washed rind category has emerged as a fast-growing segment of the marketplace. There is much anecdotal evidence to suggest a common sensorial defect in soft washed rind cheese is a gritty/sandy texture attributed to crystal growth on the rind of these cheeses

A preliminary study was undertaken to develop a set of criteria to visually identify crystals found on soft washed rind cheeses. Single crystal identities were presumptively determined using polarized light microscopy (PLM), and cross-checked using powder x-ray diffractometry (PXRD). Two distinct crystal groupings were ...


A Study Of Food Hub Buyers In Vermont: Motivation, Marketing, And Strategy, Hannah Harrington Jan 2018

A Study Of Food Hub Buyers In Vermont: Motivation, Marketing, And Strategy, Hannah Harrington

Graduate College Dissertations and Theses

Food hubs have been discussed as a promising option for scaling-up the local food system while maintaining close relationships and shared responsibility amongst producers and consumers. Food hubs have the capacity to share important messages about food safety, origin, and production methods with consumers, however little is known about if, and how, food hubs communicate the value of local food to their buyers. This is crucial when assuring value to the consumer, which is necessary for the long-term sustainability of the food hub model. It is important to know more about these methods and practices because these messages can impact ...


Do Labels Make A Difference: Estimating The Impacts Of Vermont’S Gmo Labeling Law On Perceptions And Prices, Orest V. Pazuniak Jan 2018

Do Labels Make A Difference: Estimating The Impacts Of Vermont’S Gmo Labeling Law On Perceptions And Prices, Orest V. Pazuniak

Graduate College Dissertations and Theses

Vermont is the first and only state in the US to establish mandatory labels for food containing genetically modified organisms (GMOs). This thesis investigates the impact of the mandatory labeling law as it relates to changes in prices, quantities sold, and opinions of GMOs. First, grocery store scanner data from Vermont and Oregon are compared using triple difference (difference-in-difference-in-difference) models. Next, Vermont, Oregon, and Colorado survey response data are compared using difference-in-difference models. The findings reveal that there is a general price premium for non-GMO goods of $0.05/oz across all states and times, that mandatory labeling laws do ...


Development And Implementation Of Methods To Study Crystallization In Cheese, Gil Fils Tansman Jan 2017

Development And Implementation Of Methods To Study Crystallization In Cheese, Gil Fils Tansman

Graduate College Dissertations and Theses

Dissolved compounds and ions, including mineral elements and products of microbial metabolism, are present in many cheeses in relatively high concentrations. These dissolved substances may precipitate from the aqueous phase of cheese to form sparingly soluble crystals that can impart a crunchy, gritty, or sandy texture on the cheese. In the present work, optical and diffractometric methods were optimized for use with cheese samples to identify crystal phases in several cheese varieties. These techniques, which included powder X-ray diffractometry (PXRD), single crystal X-ray diffractometry (SCXRD), and petrographic microscopy (PM) have traditionally been used on geological specimens that are quite different ...


Role Of Community Social Capital For Acute Food Security Following An Extreme Weather Event, Alana N. Chriest Jan 2017

Role Of Community Social Capital For Acute Food Security Following An Extreme Weather Event, Alana N. Chriest

Graduate College Dissertations and Theses

Worsening climate changes effects are predicted to increase the severity and frequency of extreme weather events (EWE), which can disrupt food systems, from the local to global level, and compromise community food security. In the rural U.S., food insecurity, poverty, low economic growth, and population loss are prevalent, and rural communities often lack the physical capital to bolster community resiliency to climate change adaptation. In 2011, Tropical Storm Irene (TS Irene) in Vermont was the most damaging EWE the state’s history. Severely damaged roads, infrastructure, homes, and land, rendered many rural towns isolated for up to several days ...


The Microbial Ecology Of Listeria Monocytogenes As Impacted By Three Environments: A Cheese Microbial Community; A Farm Environment; And A Soil Microbial Community, Panagiotis Lekkas Jan 2016

The Microbial Ecology Of Listeria Monocytogenes As Impacted By Three Environments: A Cheese Microbial Community; A Farm Environment; And A Soil Microbial Community, Panagiotis Lekkas

Graduate College Dissertations and Theses

This dissertation examined the microbial ecology of Listeria monocytogenes in three distinctly different environments: a cheese microbial community; a farm environment; and a soil microbial community.

The aim of the first study was to investigate the effects of L. monocytogenes on the composition of the surface microflora on washed rind soft cheese. Two trials with washed rind cheeses that were inoculated with 100cfu cm⁻² of a L. monocytogenes six strain cocktail were conducted. The first trial had to be terminated early (day 28) as contamination of Pseudomonas spp. from the initial brine did not produce the expected characteristics of ...


A Pilot Study Of The Effectiveness And Usability Of The Myenergybalance Iphone App And Website, Joanna Graff Jan 2016

A Pilot Study Of The Effectiveness And Usability Of The Myenergybalance Iphone App And Website, Joanna Graff

Graduate College Dissertations and Theses

The powerful technical capabilities of smartphones offer unprecedented opportunities for collecting dietary information. We have developed an enhanced smartphone application called MyEnergyBalance, which permits imaged-based self-monitoring of all foods consumed, and links to a convenient and user-friendly web-based dietary assessment tool. The primary objective of this pilot study was to determine if the MyEnergyBalance app (with use of images) in combination of the associated website improves dietary recall compared to diet analysis on the MyEnergyBalance website alone. We also generated preliminary data on the usability of the MyEnergyBalance iPhone app and website. This pilot study was a crossover study design ...


Food Safety Education And Disparities In North Carolina Emergency Food, Ashley Chaifetz, Benjamin Chapman Jun 2015

Food Safety Education And Disparities In North Carolina Emergency Food, Ashley Chaifetz, Benjamin Chapman

Food Systems Summit 2015

Each year, an estimated 48 million Americans (1 in 6) contract foodborne illness (Scallan, 2011) stemming from grocery stores, hospitals, day care centers, church banquets, county fairs, restaurants, private homes, schools, and even food banks (CDC FOOD, 2011). However, little research has explored the potential connection between food-insecure populations and risk of foodborne illness, especially for emergency foods (c.f. Henley et al., 2012; Koro et al., 2010; Quinlan, 2013). For the majority of people who seek food assistance, food pantries are a fixed part of food sources; that is, the pantries are for subsistence and no longer just “emergency ...


Effect Of Radiation On Polymerization, Microstructure, And Microbiological Properties Of Whey Protein In Model System And Whey Protein Based Tissue Adhesive Development, Ning Liu Jan 2015

Effect Of Radiation On Polymerization, Microstructure, And Microbiological Properties Of Whey Protein In Model System And Whey Protein Based Tissue Adhesive Development, Ning Liu

Graduate College Dissertations and Theses

Whey proteins are mainly a group of small globular proteins. Their structures can be modified by physical, chemical and other means to improve their functionality. The objectives of this study were to investigate the effect of radiation on protein-protein interaction, microstructure, and microbiological properties of whey protein-water solutions. Whey protein isolate (WPI) solutions (27-36% protein) were treated with different dosages (10-35 KGy) of gamma radiation. The protein solutions were analyzed for viscosity, turbidity, soluble nitrogen, total plate count, and yeast and mold counts. The interactions between whey proteins were also analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), and ...


Pasteurization And Its Discontents: Raw Milk, Risk, And The Reshaping Of The Dairy Industry, Andrea M. Suozzo Jan 2015

Pasteurization And Its Discontents: Raw Milk, Risk, And The Reshaping Of The Dairy Industry, Andrea M. Suozzo

Graduate College Dissertations and Theses

Milk is something many Americans consume every day, whether over cereal, in coffee or in a cup; as yogurt, cream, cheese or butter. The vast majority of that milk is pasteurized, or heated to the point where much of the bacteria in the milk dies. Pasteurization both slows spoilage of the milk and eliminates potentially harmful bacteria. The fact that we call heat-treated dairy simply "milk" is a testament to pasteurization's widespread proliferation over the past century. Prior to the 1900s, "milk" was raw and unheated, and pasteurized milk was a radically new technology. My research delved into understandings ...


Chemical Composition, Probiotic Survivability And Shelf Life Studies Of Symbiotic Buttermilk, Dong Zhang Jan 2015

Chemical Composition, Probiotic Survivability And Shelf Life Studies Of Symbiotic Buttermilk, Dong Zhang

Graduate College Dissertations and Theses

Cultured buttermilk is becoming popular as an ingredient for bakery applications and for direct consumption in the U.S.. The objective of this study was to develop a symbiotic cultured buttermilk, containing inulin as a prebiotic and the probiotics Lactobacillus acidophilus and Bifidobacterium spp. The cultured buttermilk was prepared using a commercial mesophilic starter CHN22 (Lactococcus lactis subsp. cremoris, Lactococcus lactis subsp. lactis, Leuconstoc mesenteorides subsp. cremoris, Lactococcus lactis subsp. lactis biovar diacetylactis) and the probiotics. The control buttermilk was prepared using CHN22 and the symbiotic buttermilk were analyzed for chemical composition, probiotics survivability, mold, yeast and coliform counts. Changes ...


The Impact Of Engagement With Community Supported Agriculture On Human Attitude Towards The Sustainable Food Movement, Ariana Margarita Cano Jan 2015

The Impact Of Engagement With Community Supported Agriculture On Human Attitude Towards The Sustainable Food Movement, Ariana Margarita Cano

Graduate College Dissertations and Theses

With a total of 164 community supported agriculture programs (CSA), Vermont is leading the "locavore" movement in the United States, ranked number one in the country with the most CSAs and Food Hubs per capita. ("Locavore Index," 2013)

CSAs have a large positive impact on reducing carbon emissions, advancing local economic growth, and promoting healthy lifestyles of consumers. The purpose of this study is to explore the overall experience of individuals in comparison to their current social norm, individual attitudes, identity, and intentions of change, and understand any change overtime in their individual attitude and behavior.

Attitude change was measured ...


Physicochemical Properties, Microstructure And Probiotic Survivability Of Non-Fat Goat's Milk Yogurt Using Heat Treated Whey Protein Concentrate As A Fat Replacer, James Thomas Mccarthy Jan 2015

Physicochemical Properties, Microstructure And Probiotic Survivability Of Non-Fat Goat's Milk Yogurt Using Heat Treated Whey Protein Concentrate As A Fat Replacer, James Thomas Mccarthy

Graduate College Dissertations and Theses

Probiotic dairy foods, especially non- and low-fat dairy products, are becoming popular in the US. A non-fat goat's milk yogurt containing probiotics (Lactobacillus acidophilus and Bifidobacterium spp.) was developed using heat-treated whey protein concentrate (HWPC) as a fat replacer and pectin as a thickening agent. Yogurts containing non-heat treated whey protein concentrate (WPC) and pectin as well as one with only pectin were also produced. A fat-free cow's milk yogurt with pectin was also used as a control yogurt. The yogurts were analyzed for chemical composition, water holding capacity (syneresis), microstructure, changes in pH and viscosity, mold, yeast ...


Choice, Responsibility, And Health: What Role For The Food Movement?, Nicholas Freudenberg Jun 2014

Choice, Responsibility, And Health: What Role For The Food Movement?, Nicholas Freudenberg

Food Systems Summit 2014

No abstract provided.


The Uvm Food Systems Summit Makes More Room At The Table, Jane Kolodinsky Jun 2014

The Uvm Food Systems Summit Makes More Room At The Table, Jane Kolodinsky

Food Systems Summit 2014

No abstract provided.


Racism And Capitalism: Dual Challenges For The Food Movement, Eric Holt-Giménez Jun 2014

Racism And Capitalism: Dual Challenges For The Food Movement, Eric Holt-Giménez

Food Systems Summit 2014

No abstract provided.


A Global Perspective On Food Systems, Rosamond L. Naylor Jun 2014

A Global Perspective On Food Systems, Rosamond L. Naylor

Food Systems Summit 2014

No abstract provided.


Saving Seeds: The Svalbard Global Seed Vault, Native American Seed Savers, And Problems Of Property, Sheryl D. Breen Jun 2014

Saving Seeds: The Svalbard Global Seed Vault, Native American Seed Savers, And Problems Of Property, Sheryl D. Breen

Food Systems Summit 2014

To put it simply, seeds are the essence of life. Without their varied yields, the earth would have no agriculture, no livestock, no food systems, no ecological stability. In all shapes, sizes, and distributions, seeds are genetic powerhouses that store life's codes; they are as essential a resource as the water and soil at nourish them. Nonetheless, mounting evidence demonstrates steady erosion of the seed biodiversity necessary for viable food systems. Some seed varieties have been unable to adapt as habitats change or shrink, non- commercial seed-saving techniques have disappeared along with community elders, and a relatively small number ...


High Tunnels For Local Food Systems: Subsidies, Equity, And Profitability, Nathaniel Foust-Meyer, Megan E. O'Rourke Jun 2014

High Tunnels For Local Food Systems: Subsidies, Equity, And Profitability, Nathaniel Foust-Meyer, Megan E. O'Rourke

Food Systems Summit 2014

High tunnels (HTs) constitute a growing, local level response to the globalization of our food. As semi-permanent greenhouses, HTs bring practical on-farm solutions to biophysical growing constraints; they extend the growing season and buffer delicate crops from extreme weather events. In 2009, the Natural Resource Conservation Service (NRCS) began subsidizing the construction of HTs with the documented goals of increasing environmental stewardship and the added benefit of promoting local foods. However, many questions remain about the impacts of HT’s. Who is benefiting from the NRCS HT program? Will farmers continue to adopt HTs in the absence of government subsidies ...


2013 Annual Report Of Uvm Extension And The Vermont Agricultural Experiment Station, Uvm Extension And Vermont Agricultural Experiment Station Feb 2014

2013 Annual Report Of Uvm Extension And The Vermont Agricultural Experiment Station, Uvm Extension And Vermont Agricultural Experiment Station

Annual Reports

2013 Annual report of outreach and research from UVM Extension and Vermont Agricultural Experiment Station.


Improved Recovery And Rapid Identification Of Strains, Mixed Strains, Mixed Species, And Various Physiological States Of Foodborne Pathogens Using Infrared Spectroscopy, Esmond Boafo Nyarko Jan 2014

Improved Recovery And Rapid Identification Of Strains, Mixed Strains, Mixed Species, And Various Physiological States Of Foodborne Pathogens Using Infrared Spectroscopy, Esmond Boafo Nyarko

Graduate College Dissertations and Theses

Challenges encountered in pathogen identification and detection include the genetic heterogeneity of strains within species of some foodborne pathogens, isolation of injured cells, mixed strains or mixed species contamination of foods, and differentiation between viable and dead cells. The first objective of this research was to evaluate an isolation medium that was based on time-delayed release (5 to 6 h) of selective agents in tablet format to a modified Listeria recovery enrichment broth (mLRB) medium for enhanced and rapid recovery of injured Listeria. The second objective involved the use of Fourier transform infrared (FT-IR) spectroscopy and chemometric analysis for the ...


Exploring The Nature Of Crystals In Cheese Through X-Ray Diffraction, Gil Fils Tansman Jan 2014

Exploring The Nature Of Crystals In Cheese Through X-Ray Diffraction, Gil Fils Tansman

Graduate College Dissertations and Theses

The optimization of powder x-ray diffraction (PXRD) for the study of cheese crystals was the focus of this study. A survey was conducted of various manifestations of calcium lactate crystals on the rindless surface and within mechanical openings of Cheddar cheese using PXRD. The diffraction reference card database contained a card that was entitled calcium lactate pentahydrate and corresponded to some of the crystalline material found on the cheeses. Diffractions patterns generated from other samples of crystalline material revealed the existence of an unknown crystal that resembled and behaved similarly to calcium lactate pentahydrate, but did not match the reference ...


Functional Properties Of Whey Protein And Its Application In Nanocomposite Materials And Functional Foods, Helen Walsh Jan 2014

Functional Properties Of Whey Protein And Its Application In Nanocomposite Materials And Functional Foods, Helen Walsh

Graduate College Dissertations and Theses

Whey is a byproduct of cheese making; whey proteins are globular proteins which can be modified and polymerized to add functional benefits, these benefits can be both nutritional and structural in foods. Modified proteins can be used in non-foods, being of particular interest in polymer films and coatings. Food packaging materials, including plastics, can linings, interior coatings of paper containers, and beverage cap sealing materials, are generally made of synthetic petroleum based compounds. These synthetic materials may pose a potential human health risk due to presence of certain chemicals such as Bisphenol A (BPA). They also add to environmental pollution ...