Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 13 of 13

Full-Text Articles in Life Sciences

Observed Defects Of Swiss Cheese Based On The Microbiome Contribution To The Production Of Organic Acids, Vannessa D. Campfield Dec 2020

Observed Defects Of Swiss Cheese Based On The Microbiome Contribution To The Production Of Organic Acids, Vannessa D. Campfield

Boise State University Theses and Dissertations

The United States Department of Agriculture downgrades on the order of 17% of all Swiss cheese produced in the United States due to defects. Many of these defects are related to improper eye formation, number, distribution, or size; leading to an industry loss of over $69 million per annum. The microbiome in Swiss-type cheeses plays a significant role in eye development due to production of organic acids and gaseous emissions contingent on bacterial abundance and phenotype. The relationship between bacteria and the organic acids they produce leading to Swiss cheese defects can be correlated using Next-generation sequencing and high-performance liquid …


Biogenic Amines As A Product Of The Metabolism Of Proteins In Beer, Hayden Koller Aug 2020

Biogenic Amines As A Product Of The Metabolism Of Proteins In Beer, Hayden Koller

Electronic Theses and Dissertations

For many years the only beer that was commercially available in the United States were simple lagers and ales made primarily of barley (and other cereals), water, hops, and yeast. These beer varieties were simple and quick to produce with high levels of consistency. In the last 30 years the rise in craft and microbreweries have dramatically changed the landscape of brewing and beer. As smaller breweries rose in popularity so did the use of unique ingredients such as vegetables, fruits, herbs, meat, etc. along with higher gravity mashes and long barrel aging times. All these ingredients have a profound …


Microbial Diversity Of The Symbiotic Colony Of Bacteria And Yeast (Scoby) And Its Impact On The Organoleptic Properties Of Kombucha, Danielle L. St-Pierre Aug 2019

Microbial Diversity Of The Symbiotic Colony Of Bacteria And Yeast (Scoby) And Its Impact On The Organoleptic Properties Of Kombucha, Danielle L. St-Pierre

Electronic Theses and Dissertations

Kombucha is an effervescent fermented tea beverage that is gaining popularity for its probiotic nature and purported health benefits. The market for kombucha is expected to reach $1.8 billion by the year 2020. The composition of microbes that compose the symbiotic colony of bacteria and yeast (SCOBY) is highly variable with some species commonly found from the Gluconobacter, Acetobacter, Zygosaccharomyces, Saccharomyces, and Schizosaccharomyces genera.

It was hypothesized that different SCOBYs, obtained from different sources would vary in microbial diversity and produce different biochemical and flavor profiles in the resulting beverage over several generations. Kombucha is a fermented …


Anthocyanin Stability In Food Products Made With Freeze-Dried Blueberry Powder, Samantha Findley May 2019

Anthocyanin Stability In Food Products Made With Freeze-Dried Blueberry Powder, Samantha Findley

Food Science Undergraduate Honors Theses

This study evaluated the stability of anthocyanins in six blueberry products (gummy, graham bar, oatmeal bar, rice krispy bar, ice pop and juice) prepared with freeze-dried wild blueberry powder during processing and over eight weeks storage. Total anthocyanins were determined by HPLC before processing and at day 0 and 2, 4, 6, and 8 weeks of storage. Thermal processing of gummy and graham bar products resulted in significant losses of anthocyanins (50% and 31%, respectively). An eight-week storage time also resulted in a significant decrease in anthocyanins (7% to 51%) in products stored at ambient temperature. The ice pop, which …


Extraction And Purification Of (E)-Resveratrol From The Bark Of Maine's Native Spruces, Panduka S. Piyaratne May 2018

Extraction And Purification Of (E)-Resveratrol From The Bark Of Maine's Native Spruces, Panduka S. Piyaratne

Electronic Theses and Dissertations

Resveratrol is a plant secondary metabolite which protects plants from pathogenic invasions and acts as a remedial agent against injury, stress, and tissue damage by UV radiation. With its characteristic stilbene structure, resveratrol adopts (E) and (Z) isomeric forms. However, the (E) isomer is the most biologically active and abundant form of resveratrol in nature.

(E)- Resveratrol confers a variety of benefits to human health and well-being. Besides its antioxidant activity, the role of (E)-resveratrol as an anti-inflammatory, anti-aging, cardioprotection, and anticancer agent has been a widely explored research interest. …


Characterization And Mechanisms Of Anthocyanin Degradation And Stabilization, Nathan Blaine Stebbins Dec 2017

Characterization And Mechanisms Of Anthocyanin Degradation And Stabilization, Nathan Blaine Stebbins

Graduate Theses and Dissertations

Anthocyanins (ACYs) are polyphenol compounds found in nature, which contribute vivid colors to many fruits and vegetables, while also possessing significant health benefits. These pigments range in color from orange-red to blue-violet and could serve as natural colorants to replace artificial additives. There is a great demand from consumers to have fewer artificial compounds in their foods. However, the relatively instability of ACYs must be further understood in order to limit color degradation before they can completely replace synthetic colorants.

ACYs slowly degrade over time, but there is a knowledge gap on their fate and mechanisms causing degradation. In order …


Method Development For Vitamin C Quantification In Two Complex Matrices, Hannah D. Hutt Aug 2015

Method Development For Vitamin C Quantification In Two Complex Matrices, Hannah D. Hutt

Electronic Theses and Dissertations

The following liquid chromatographic (LC) method developments and applied research studies were done using two complex food matrices, potatoes and elderberries, which are common to the state of Maine. Potatoes are Maine’s largest agricultural crop, a staple food in most U.S. households, and are, from an analytical standpoint, considered a complex matrix due to the high starch content that can be difficult to remove without degrading or removing nutrients in the process. Elderberries are an emerging crop in the U.S. because of their antioxidant and anti-viral properties and are found growing wild, throughout Maine. Elderberries are also considered a complex …


Chemical Separation And Analyses Of Bioactive Compounds In Chloroform Fraction Of Oplopanax Horridus (Devil's Club), Lauren Wiseman May 2015

Chemical Separation And Analyses Of Bioactive Compounds In Chloroform Fraction Of Oplopanax Horridus (Devil's Club), Lauren Wiseman

All Theses

O. horridus (a member of the family Araliaceae) is a plant traditionally used by the tribe of Pacific Northwest America for medicinal as well as spiritual purposes. O. horridus is found in the temperate forests of northwestern North America as an understory shrub capable of growing in well-drained to poorly drained, shady sites. Traditional medical preparations of O. horridus include decoction or infusion, preparation as a tea, preparation as a poultice, or preparation as a tonic. O. horridus is used as a form of treatment for cancer, hypoglycemia, diabetes, tough pneumonia, and for colds. A practical and reliable extraction method …


Changes In Monomeric And Polymeric Pigments During Chokeberry Juice Processing, Kail David Wilkes Dec 2014

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 …


Development And Application Of Scalable Two-Dimensional High Performance Liquid Chromatography For Aromatic Selective Separations Of Biologically Active Phytochemicals From Oplopanax Horridus, Gregory Jones Dec 2014

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 …


Development Of Hplc Methods For The Determination Of Water-Soluble Vitamins In Pharmaceuticals And Fortified Food Products, Hung Khiem Trang Aug 2013

Development Of Hplc Methods For The Determination Of Water-Soluble Vitamins In Pharmaceuticals And Fortified Food Products, Hung Khiem Trang

All Theses

Though many HPLC methods have been developed and reported in literature for vitamin analysis for the past two decades, applying certain methods directly from literature more than often fails to reproduce the results reported due to many variables of liquid chromatography. This issue was targeted in this project through the examination of chromatographic behaviors of water-soluble vitamins in order to help the analysts better modify methods from literature or even develop new methods from scratch to fit their analytical need with the resources available (e.g., columns, detectors, etc.) in their lab.
The first part of the project investigated the chromatographic …


Biological Properties Evaluation And Chemical Profiles Of Phenolic Compounds In Muscadine Grapes (Vitis Rotundifolia), Qi You May 2012

Biological Properties Evaluation And Chemical Profiles Of Phenolic Compounds In Muscadine Grapes (Vitis Rotundifolia), Qi You

All Dissertations

Phenolic compounds, including anthocyanins in muscadines have attracted much attention due to their diverse biological activities. With bioassays of antioxidant activities in terms of total phenolic content (TPC), total flavonoid content (TFC) total anthocyanin content (TAC), total procyanidin content (TPA), oxygen radical absorbance capacity (ORAC), ABTS radical scavenging Activity (ABTS), ferric reducing antioxidant power (FRAP), and oil peroxidation inhibitory capacity of all muscadine samples, the muscadine grapes showed strong antioxidant activities. The liquid-liquid organic solvent extraction successfully separated the anthocyanins and other phenolics to different fractions. Strong linear relationship between responses of TPC, TAC and TPA versus their antioxidant activities …


Reversed-Phase Hplc Determination Of Alliin In Diverse Varieties Of Fresh Garlic And Commercial Garlic Products., Aaron Kwaku Apawu Aug 2009

Reversed-Phase Hplc Determination Of Alliin In Diverse Varieties Of Fresh Garlic And Commercial Garlic Products., Aaron Kwaku Apawu

Electronic Theses and Dissertations

Alliin is a predominant flavor precursor in garlic cloves. It interacts with the enzyme alliinase when garlic cloves are crushed, cut, or chewed to produce allicin, an unstable thiosulfinate that is the main biologically active component of fresh crushed garlic. Biological functions and health benefits of garlic include reduction of cancer risk in humans, improving immune system, and anti-microbial, anti-oxidant, and anti-hypertensive activities. The quality of fresh garlic and garlic products is usually related to its alliin content and allicin release potential. This research presents a simple, rapid, and precise HPLC method for alliin determination. It involves the use of …