Food Chemistry Commons^™

Allosteric And Uncompetitive Inhibition Of Yeast Alcohol Dehydrogenase Identified By Enzyme Kinetics, Dylan Jeremy Harrison, Jenny A. Cappuccio

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Cal Poly Humboldt

Enzyme kinetics is a powerful technique used to quantify the rate at which an enzyme converts a substrate into a product and to identify potential inhibitors. In this study, kinetic analysis was employed to assess the activity of yeast alcohol dehydrogenase (YADH) in the presence and absence of sweeteners commonly found in alcoholic beverages. YADH catalyzes the oxidation of ethanol to acetaldehyde using NAD⁺ as a cofactor; the reduction to NADH can be monitored spectrophotometrically at 340 nm. Based on structural similarities to the ribose moiety of NAD⁺, it was hypothesized that sucrose and sucralose could directly interact with the …

Analysis Of The Flavonoid Composition Of Honey Using High-Performance Liquid Chromatography, Bryce Phillips

Honors Theses

Honey is a naturally occurring substance that has a complex composition including compounds such as flavonoids, that contribute to potential health benefits. Quantitative analysis of flavonoids in honey can be challenging due to their similar structural characteristics, matrix effects, and chromatographic peak separation issues. This study aimed to establish calibration curves for five flavonoids–kaempferol, luteolin, chrysin, myricetin, and quercetin– to estimate their concentrations in five honey samples from varying geographic origins. Liquid-liquid extraction was used to isolate the flavonoids from honey. High Performance Liquid Chromatography was utilized to establish calibration curves and analyze honey samples. The calibration curves assembled demonstrated …

Photoflow Synthesis And Characterization Of Cis- And Trans-N-Isohumulone, Gregory M. Giovine, Bradley Gallow, Trevor Smith, Bruce Hamper

Undergraduate Research Symposium

Previously published efforts by the Hamper group demonstrated the viability of photochemistry in the isomerization of n-humulone to n-isohumulone. Photochemical isomerization reactions of n-humulone performed under 400nm light over 8 hours resulted in high yields (84% reported) of largely trans-n-isohumulone (>95%). These promising results invited further examination of the photochemical process and the application of photoflow procedure. Herein we report the beginnings of a comprehensive slate of n-humulone isomerization reactions performed under iterative photoflow conditions.

Design And Application Of Smart Systems To Address Analytical Problems, Lucas B. Ayres

All Dissertations

This dissertation is a multidisciplinary effort that integrates low-cost analytical instrumentation, redox chemistry, and artificial intelligence to overcome existing limitations in the fields of wearable sensing technology, Deep Eutectic Solvents (DES), and antioxidant chemistry. The overall goal behind each implemented strategy is to enhance the accuracy, efficiency, and accessibility of analytical processes and technologies. A general overview of the thesis, along with the research outcomes is included in Chapter One. The theoretical framework of this dissertation is presented in Chapter Two. Chapter Three describes the development of a wearable platform (sensor and instrumentation) to rapidly detect (~20 minutes) S. aureus …

Physicochemical Changes And Role Of Analytical Chemistry In Black Garlic (Allium Sativum L.) Processing, Surjani Wonorahardjo, Dian Puspita Sari, Arini Salsabila, Estiyawati Estiyawati, Dewi Yuliani, Anugrah Ricky Wijaya, Suharti Suharti, Irma Kartika Kusumaningrum, Chariztya Anggita Maharani, Thjiong Angelina Noviyanti

Makara Journal of Science

Black garlic is a traditional spice having potential of herbal medicine; however, continuous heating darkens its color and changes its taste due to chemical processes and new equilibrium in the system. In this study, fresh garlic was processed into black garlic at 60 °C for 24 days. Changes in physical and chemical parameters, such as browning and protein content, reducing sugar content, and antioxidative components were recorded. Protein content was measured by Kjeldahl method, brown color development was analyzed using a color reader, reducing sugar was examined using a dinitro salicylic DNS reagent, and antioxidative activities were studied with a …

Food Waste Storage Gaseous Emissions Detection And Quantification Using Infrared Spectroscopy, Ryley A. Burton-Tauzer

Cal Poly Humboldt theses and projects

A growing interest in sustainable waste management and the implementation of new policies have prompted a shift towards alternative resource recovery methods for organic waste, including food waste. To effectively assess alternative food waste treatment scenarios, it is important to evaluate the life cycle impacts associated with each scenario. The storage phase of food waste, encompassing its accumulation in kitchens, and storage in bins for collection and transportation, has been overlooked as a source of greenhouse gases in previous studies. This investigation aimed to identify the greenhouse gases emitted during the initial five-day period of low-oxygen storage. An open dynamic …

Application Of Mass Spectrometry For Characterization Of Plant-Based Phenolics And Alkaloids, Masoumeh Dorrani

Theses and Dissertations--Chemistry

Plant-derived compounds have the potential to produce value-added compounds with a variety of applications. For example, the lignin part of the lignocellulosic biomass, produced in large quantities as waste from the paper and pulp industries, is a rich source of phenolics with potential applications in the renewable energy sector, pharmaceutical, and chemical industries. On the other hand, plant alkaloids are the primary source for developing plant-derived therapeutics. Unfortunately, the recalcitrant nature of plant cell walls, low extraction yields of small secondary metabolites, and the lack of effective analytical methods for a rapid and accurate identification of plant-based compounds and plant’s …

Bioanalytical Determination Of Glucose Concentration In Sports Drinks Using Uv/Vis Spectroscopy, Laney Hedgeman, Brianna Bond

Symposium of Student Scholars

Abstract

The purpose of our project is to indirectly monitor the enzymatic activity of glucose oxidase as it reacts with the glucose present in sports drinks through the quantitative analysis of the generated ferricyanide. As glucose oxidase catalyzes the oxidation of beta-D-glucose in the presence of oxygen, D-glucono-1,5-lactone is produced along with hydrogen peroxide. The hydrogen peroxide is used in a subsequent reaction with ferrocyanide catalyzed by horse radish peroxidase to produce water and the chromophore ferricyanide. This compound absorbs in the ultraviolet/visible spectrum at 420 nm, which can be quickly measured using Ultraviolet/Visible Spectroscopy. Since the molar ratio of …

Three-Way Analysis-Based Ph-Uv-Vis Spectroscopy For Quantifying Allura Red In An Energy Drink And Determining Colorant's Pka, Erdal Dinç Prof., Nazangül Ünal, Zehra Ceren Ertekin

Journal of Food and Drug Analysis

Three-way analysis-based pH-UV-Vis spectroscopy was proposed for quantifying allura red in an energy drink product without the need for chromatographic analysis, and determining the colorant’s pKa without using any titration technique. In this study, UV-Vis spectroscopic data matrices were obtained from absorbance measurements at five different pH levels from pH 8 to pH 12 and arranged as a three-way array (wavelength x sample x pH). In the three-way analysis procedure, parallel factor analysis (PARAFAC) was implemented to decompose the three-way array into a set of trilinear components. Each set of three components relates to spectral, pH and relative concentration profiles …

Valorization Of Xylan In Agroforestry Waste Streams, Harrison Appiah

Graduate Theses, Dissertations, and Problem Reports (ETD)

Valorization of Xylan in Agroforestry Waste Streams.

Harrison Appiah

Microwave-assisted deep eutectic solvent and gamma-valerolactone metallic chloride catalyzed conversion of xylan to furfural were investigated using a 2x3 factorial experimental design at two levels of percent microwave power, reaction time, and catalyst concentration. The levels of each factor studied were (20%, 60% microwave power, 2, 4 minutes, and 10, 20mg) respectively. The effect of three metallic chloride catalysts (LiCl, FeCl3.6H20, CuCl2) on the conversion of xylan to furfural was also investigated. The gamma-valerolactone-ferric chloride sent system exhibited the highest mean yield of furfural (56.50%). The next highest furfural yield of …

Online Ultra-High Performance Liquid Chromatography-Charge Transfer Dissociation-Mass Spectrometry (Uhplc-Ctd-Ms) Of Complex Mixtures Of Oligosaccharides, Praneeth M. Mendis

Graduate Theses, Dissertations, and Problem Reports (ETD)

Abstract

Online Ultra-High Performance Liquid Chromatography-Charge Transfer Dissociation-Mass Spectrometry (UHPLC-CTD-MS) of Complex Mixtures of Oligosaccharides

Praneeth M. Mendis

Complex carbohydrates make up more than half the biomass on earth, and they are crucial to a wide range of processes in living organisms. When polysaccharides and glycans are enzymatically digested into manageable units called oligosaccharides, they typically consist of 2-20 linear or branched sugar units. The detailed structural analysis of oligosaccharides assists in the identification of structural and chemical properties of the polymers from which they derive. Tandem mass spectrometry (MS/MS) is a key technique used in oligosaccharides structural characterization. Within …

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 …

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 …

Spheroid-3d And Monolayer-2d Intestinal Electrochemical Biosensor For Toxicity/Viability Testing: Applications In Drug Screening, Food Safety, And Environmental Pollutant Analysis, Evangelia Flampouri, Shahzad Imar, Kieran O'Connell, Baljit Singh

Articles

The rise of three-dimensional cell culture systems that provide in vivo-like environments for pharmaco-toxicological models has prompted the need for simple and robust viability assays suitable for complex cell architectural structures. This study addresses that challenge with the development of an in vitro enzyme based electrochemical sensor for viability/cytotoxicity assessment of two-dimensional (2D) monolayer and three-dimensional (3D) spheroid culture formats. The biosensor measures the cell viability/toxicity via electrochemical monitoring of the enzymatic activity of nonspecific esterases of viable cells, through the hydrolysis of 1-naphthyl acetate to 1-naphthol. The proposed sensor demonstrated strong correlation (r = 0.979) with viable …

Application Of Analytical Techniques In Food Product Development, Sonali R. Pandey

Electronic Theses and Dissertations

Products are analyzed in major sectors of food industry to meet regulatory standards, food safety, quality control, and research and development. Analytical and extraction techniques have been applied for simultaneous investigation of multiple product characteristics. Food analysis faces critical challenges due to the complex composition of food, leading to matrix effects that result in loss of accuracy and reliability. The analytical techniques require an efficient sample preparation to avoid or minimize matrix effects. Solid-phase extraction has been widely used to address this issue. In this dissertation, the aim is to apply analytical techniques in food product development. To accomplish this, …

Anthocyanin Stability In Food Products Made With Freeze-Dried Blueberry Powder, Samantha R. Findley, Luke Howard

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

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 losses of anthocyanins (50 and 31%, respectively). An eight-week storage time also resulted in a decrease in anthocyanins (7 to 51%) in products stored at ambient temperature. The ice pop, which was stored …

Rapid Analysis Of Magnesium In Infant Formula Powder Using Laser-Induced Breakdown Spectroscopy, Maria Markiewicz-Keszycka, Ming Zhao, Xavier Cama-Moncunill, Toufic El Arnaout, Dana Becker, Colm O'Donnell, P. J. Cullen, Carl Sullivan, Maria Piedad Casado-Gavalda

Articles

Laser-induced breakdown spectroscopy (LIBS) was investigated to determine magnesium (Mg) content in infant formula powder. To predict Mg content in the range established by the Codex Alimentarius, a partial least squares regression (PLSR) model was developed using a calibration data set (n = 30) based on full cross-validation and validated using an independent validation data set (n = 21). The prediction model performance was evaluated using the regression coefficients of determination (Rcv2 = 0.94 and Rp2 = 0.85) with the root mean square errors on cross-validation and prediction (RMSECV = 60 mg kg−1 and RMSEP = 80 mg kg−1). The …

The Effects Of Cold Plasma Treatment On Sweet Basil (Ocimum Basilicum), Sauvelson Auguste

Seton Hall University Dissertations and Theses (ETDs)

The study discussed herein looks both to continue and to expand upon previous work conducted here at Seton Hall University, which investigated the effect of cold plasma processing on sweet basil and their essential oils. It was found that the application of cold plasma treatment increases plant growth and eugenol concentration, which is an essential oil component and one of the potential natural antioxidants used in food preservation. In this study, we considered methods for increasing the production and harvesting of plants that produce essential oils such as sweet basil (Ocimum basilicum). The study also incorporated more controls …

Eating Crickets? Nutrient Mineral Content Of Two Cricket Species And Chapul Cricket Protein Bars Using Mp-Aes, Nathan Hopkins

Student Scholar Showcase

Global agriculture is beset by numerous challenges which must be surmounted to feed a developing world, from combating climate change to the cultivation of sustainable food products. This, in addition to protein and nutrient deficiencies in the developing world, makes considering alternative protein sources, such as a crickets, an attractive option. Crickets use a fraction of the land and water that protein sources like beef cattle do, and can be cultivated in urban environments in stacked boxes. This research investigation aims to quantify the nutrient mineral content (Iron, Sodium, Potassium, Calcium, and Magnesium) of two cricket species (Acheta domesticus …

The Therapeutic Potential Of Natural Products From Vaccinium Berries For Viral And Lung Diseases Through An Improved Lc-Ms-Based Chemometric Approach, Vanya I. Petrova

Dissertations, Theses, and Capstone Projects

Smoking is a global epidemic that creates serious health and economic burden. It is the primary, preventative factor for the majority of causes of death worldwide. Analysis of publicly available data revealed that smoking prevalence rates among the youth in developing countries, especially in Bulgaria, are alarmingly high. The Bulgarian population has one of the highest percentages of smokers and the second highest rate among teenage girls. Consequently, chronic diseases affected by smoking, such as chronic obstructive pulmonary disorder (COPD), have been increasing there in the last five years. Poland, on the other hand, is an exemplary outlier for the …

Reactivity Of Ketyl And Acetyl Radicals From Direct Solar Actinic Photolysis Of Aqueous Pyruvic Acid, Alexis J. Eugene, Marcelo I. Guzman

Chemistry Faculty Publications

The variable composition of secondary organic aerosols (SOA) contributes to the large uncertainty for predicting radiative forcing. A better understanding of the reaction mechanisms leading to aerosol formation such as for the photochemical reaction of aqueous pyruvic acid (PA) at λ ≥ 305 nm can contribute to constrain these uncertainties. Herein, the photochemistry of aqueous PA (5-300 mM) continuously sparged with air is re-examined in the laboratory under comparable irradiance at 38° N at noon on a summer day. Several analytical methods are employed to monitor the time series of the reaction, including (1) the derivatization of carbonyl (C═O) functional …

Metabolic Profiling Of Genetically Modified Potato Periderm Tissues, Liqing Jin

Dissertations, Theses, and Capstone Projects

Potato tubers are protected from dehydration and pathogens by a covering peel (periderm) impregnated with suberin, a complex cross-linked biopolymer that contains both polyaliphatic and lignin-like aromatic domains. Current models describing the macromolecular structure of suberin assume that ferulic acid cross-links both domains as it may form carboxyl ester bonds with aliphatic monomers and non-ester radical-coupled bonds with phenolics. Ferulic acid also links by ester bonds to glycans and acts in cross-linking polysaccharides and lignin. Fatty alcohol/ω-hydroxyacid hydroxycinnamoyl transferase (FHT) is a BADH acyltransferase responsible for the synthesis of akyl-ferulates that is necessary for suberin biosynthesis. Periderm from FHT-RNAi …

Investigation Of Pyrrolizidine Alkaloids In Foods Using Liquid Chromatography Mass Spectrometry, Caroline Griffin

PhDs

Pyrrolizidine Alkaloids (PAs) are known plant toxins which can cause hepatic veno-occlusive disease (HVOD) in both humans and livestock when ingested. Although PAs are primarily known for their hepatotoxicity they also induce genotoxicity, carcinogenicity and pneumotoxicity. PAs are consumed through plants as food, for medicinal purposes, or as contaminants of agricultural crops. Aside from ingesting the plants directly PA exposure may occur through the consumption of honey produced by bees that visit PA-containing plants or by drinking milk produced by animals that have consumed PA-containing plants. Possible PA contamination in our food chain is a potential health risk.

To assess …

Strawberry Growth, Yield, Fruit Nutrition, And Control Of Verticillium Wilt With Pre-Plant Soil Fumigants, Ozone, And Biological Control, Justin J. Scurich

Master's Theses

Verticillium wilt is a widespread soilborne disease of strawberry historically controlled by soil fumigation with methyl bromide (MB). MB was banned by the United Nations in 1995 and will be completely phased out by 2015. Research has concentrated on alternative methods of disease control without finding a single alternative able to replace MB in widespread disease control and yield increase. For the current study, strawberries were greenhouse grown in container pots filled with soil from both infested and non-infested areas of a commercial strawberry field in Watsonville, CA. Treatments included pre-plant soil fumigation with commercially available formulations of methyl bromide, …

Investigation Of Factors Influencing Trichloromethane Levels In Milk And Its Control., Siobhan Ryan

Theses

Trichloromethane (TCM) is an undesirable chemical residue that can develop in milk. While TCM levels in milk are not within ranges of public health concern, it is important that minimal levels are maintained in order to promote the marketing of Irish dairy products abroad. Germany has enacted strict regulations on TCM concentrations in foodstuffs with a recommended level of0.002 mg/kg and re-analyse those milks, subsequent to cause identification and provision of advice on reducing TCM levels in milk. Milk samples were analysed using Gas chromatography (GC) with electron capture detection. The GC method was adapted and a standard curve was …

Development And Validation Of A Rapid Multi-Class Method For The Confirmation Of Fourteen Prohibited Medicinal Additives In Pig And Poultry Compound Feed By Liquid Chromatography Tandem Mass Spectrometry, Mark Cronly, Patrice Behan, Barry Foley, Liam Regan, Marella Gallagher, Sean Earley, Paula Shearan, Edward Malone

Articles

A confirmatory method has been developed to allow for the analysis of fourteen prohibited medicinal additives in pig and poultry compound feed. These compounds are prohibited for use as feed additives although some are still authorised for use in medicated feed. Feed samples are extracted by acetonitrile with addition of sodium sulphate. The extracts undergo a hexane wash to aid with sample purification. The extracts are then evaporated to dryness and reconstituted in initial mobile phase. The samples undergo an ultracentrifugation step prior to injection onto the LC-MS/MS system and are analysed in a run time of 26 minutes. The …

Rapid Multi-Class Multi-Residue Method For The Confirmation Of Chloramphenicol And Eleven Nitroimidazoles In Milk And Honey By Liquid Chromatography Tandem Mass Spectrometry, Mark Cronly, Patrice Behan, Barry Foley, Liam Regan, Sheila Martin, Michael Doyle, Edward Malone

Articles

A confirmatory method has been developed to allow for the analysis of eleven nitroimidazoles and also chloramphenicol in milk and honey samples. These compounds are classified as A6 compounds in annex IV of council regulation 2377/90 and therefore prohibited for the use in animal husbandry. Milk samples are extracted by acetonitrile with addition of NaCl, while honey samples are first dissolved in water before a similar extraction. Honey extracts undergo a hexane wash to remove impurities. Both milk and honey extracts are evaporated to dryness and reconstituted in initial mobile phase. These are then injected onto an LC-MS/MS system and …

Determination Of Lead, Cadmium, Zinc And Nickel Inedible Oil Products By Stripping Voltammetry., Ng Khan Loon

Student Works (2010-2019)

Edible oil products had become an everyday food that been consumed by most of the people either for dressing or for cooking purpose. Metal has become a common contamination to the food product, which it found the way into the edible oil through environment and processing contamination such as crushing, distillation, and hydrogenation. In this Study, the main focuses of metal analysis are only confined to 4 common metals which are the Cadmium, Lead, Zinc and Nickel. These elements are selected in this study due to reason that Cadmium and Lead are commonly known for their contamination from environment and …

Optimization Of Solid-Phase Microextraction For The Determination Of Organo-Phosphorus And Organo-Chlorine Pesticide Residues In Natural Water Near Aquaculture Farms., Chan Chun Foong

Student Works (2010-2019)

The global shrimp farming industry had a rapid growth in the 1980s due to the high demand for shrimp. Apart from the destruction of mangroves and wetlands, the intensive operation of shrimp aquaculture deteriorated the water quality in the region. Variety of chemicals and biological products were used to prevent the outbreaks of diseases in the intensively managed shrimp ponds. Pesticides were used as disinfectands to kill unwanted organisms in the pond. SPME-GC-ECD method was developed for the determination of azinphos-ethyl, chlorphyrifos-methyl, diazinon, dichlorvos, endosulfan-I, endosulfan-II, endosulfan sulfate and malathion from water samples of shrimp aquaculture area in Manjung district, …