Food Science Commons^™

The Effect Of Specialty Malt On Dry-Hopping, Alexander Kivela

Master's Theses

Dry-Hopping is a modern and ever-increasing method to add hoppy flavors to beer. This is typically seen in pale ales and India Pale Ales (IPA’s). Most research has investigated the effect of dry-hopping only using pale malt, whereas most breweries used specialty malts to create a malty backbone to their beer.

The objectives of this research were to analyze the impact of specialty malts and their concentration on the efficacy of hop flavor and extraction, determined via gas chromatography and sensory analysis. Gas chromatography analysis was modeled after the ASBC Method Beer-48. Sensory analysis was performed via the 15cm line …

Evaluating The Impact Of Region, Vintage, And Carbon Dioxide-Based Winemaking Techniques On Wine Quality Of Mediterranean Varietals, Coleman R. Imrisek

Master's Theses

Changing Vitis vinifera ripening patterns as a result of increasing climate variability has provided challenges against the production of wines with a balanced sensory profile, with adequate acidity, color, aroma, and texture. This thesis aimed to evaluate the ripening patterns and wine profiles of potentially climate-adaptive Mediterranean varietals in two different California Central Coast climates. Additionally, different carbon-dioxide based winemaking techniques were also assessed. Viognier and Grenache Noir grapes were sourced from the warmer, diurnal Paso Robles AVA and the cooler, marine Santa Maria AVA during the 2024 and 2025 growing seasons, with Syrah and Grenache Blanc grapes being only …

The Effects Of Maceration And Enzymes On The Chemical Characteristics Of Hard Apple Cider, Manou De Pelsmaeker

Master's Theses

The purpose of this study was to analyze the effects of maceration and pectinase enzymes on the base chemical, polyphenolic, and volatile characteristics of cider. The apples (Fuji) were milled and macerated for 0, 4, 12, 24, or 36 hours, both with and without an enzymatic pectinase addition. While base chemical characteristics such as sugar content and ABV were unaffected, the acidity of cider was influenced maceration and enzymes. Extended maceration time resulted in lower concentrations of malic acid, and enzymes resulted in a lower pH compared to the control. Polyphenols were extracted during maceration time, resulting in higher concentrations …

Exploring Non-Conventional Substrates: The Role Of Hibiscus And Whey In Kombucha Fermentation, Benjamin J. Lee

Master's Theses

This study evaluated the impact of hibiscus and whey as alternative fermentation substrates on the physicochemical, phytochemical, and microbial properties of kombucha. A 2 × 2 full factorial design was used to compare four treatments: black tea + water (BW), black tea + whey (BH), hibiscus + water (HW), and hibiscus + whey (HH). The fermentation solvents (water or whey) were heated to 88 °C, infused with 0.6% (w/v) black tea or hibiscus for 10 minutes, sweetened with 10% (w/v) sucrose, cooled to 22 °C, and inoculated with 20% (v/v) kombucha starter culture. Fermentations were carried out at 22 °C …

Protein Digestibility Impacted By Bacillus Coagulans, Pasteurization And Protein Source In Ready-To-Drink Protein Beverages, Samantha L. Bass, Samantha L. Bass

Master's Theses

The goal of this study was to assess how to maximize the digestibility of protein in protein beverages utilizing various protein sources, differing temperature/storage combinations, and the addition of probiotics (Bacillus coagulans). The protein sources used included 3 milk proteins and 2 plant protein sources (micellar casein, milk protein concentrate, reduced-calcium milk protein concentrate, pea protein isolate, and soy protein isolate). Soy protein isolate was chosen because it is readily available and commonly used as a plant protein alternative. Pea protein isolate was chosen because it is a non-allergen, and similarly, it is readily available. Milk protein concentrates …

Development Of Extruded Puffed Snack Utilizing Carrot Pomace, Bean Flour, And Rice Starch As Primary Ingredients, Julia Zoe

Master's Theses

Every year, the carrot industry worldwide wastes up to 50% of carrots as raw material due to processing (Šeregelj et al., 2020). When carrots are juiced, the remaining fibrous pulp is often discarded as carrot pomace. In order to redirect this food waste, the first objective of this research was to optimize formulations for an extruded puffed snack that is most similar to commercially available puffed snacks, utilizing baby lima bean flour and carrot pomace

Hardness (kg), cross-sectional expansion ratio, bulk density (g/cm³), moisture content (%), water activity, specific mechanical energy (kJ/kg), carotenoid concentration (ppm), and total dietary …

Red Raspberries Attenuate Blood Glucose Spike Of A High Glycemic Load Breakfast Cereal, Dante J. Martin

Master's Theses

Blood glucose (BG) spikes increase chronic disease risk in those with and without diabetes. The fiber and phytonutrient content of fruit, such as raspberries has the potential to attenuate the BG spike of a high glycemic load (HGL) meal. We examined the effect of red raspberries (RRs) on the BG spike when added to a HGL meal. In this randomized cross-over trial, 16 university students were given breakfast cereal and almond milk (control), the control breakfast with 140g added RRs, and the control breakfast with sugar equivalent to the sugar content of the RRs (50% sugar increase from control). Meals …

Physical Treatments To Modify The Functionality Of Carrot Pomace And The Development Of An Enhanced Beef Patty, Jordan O.A Richards

Master's Theses

Approximately one-third of the global food produced for human consumption is lost or wasted somewhere along the food chain. Carrots are one of the most important and widely produced root vegetables grown worldwide; they are rich in many beneficial bioactive compounds such as dietary fiber and carotenoids. Every year, an estimated 29% of processed carrots are lost as waste. The U.S. is the 3^rd largest producer of carrots worldwide, 85% of which come from California. During carrot juice processing, up to 50% of the raw material remains as carrot pomace. Carrot pomace may contain up to 55% total dietary …

Evaluation Of Potential Surrogates For Listeria Monocytogenes In Fresh Citrus-Specific Validation Studies, Kimiko Grace Casuga

Master's Theses

The FSMA Produce Safety Rule (PSR) requires citrus packers to more closely assess, manage, and monitor food safety risks. Although there have been no foodborne illness outbreaks and only one recall in fresh citrus, the risk of pathogens coming in on the fruit and cross contamination during washing still exists. Packhouses have dynamic washing systems and in-plant validations may be the only way to demonstrate compliance with the PSR. In-plant validations use surrogates in place of pathogens, and none have been identified or validated for citrus. The aim of this research was to identify a surrogate for use in fresh …

Cofermentation, Post-Alcoholic, And Post-Malolactic Fermentation Blending Of Malbec, Merlot And Petite Sirah Wines, Armando Arturo Vega-Osorno

Master's Theses

A two-year study was conducted to assess the effects of cofermentation on red wine varietals. During the winemaking process, wines can be made from two or more varieties by picking, crushing and fermenting them together, a practice known as cofermentation. They can also be blended either after the completion of alcoholic fermentation or after malolactic fermentation. In the first year of the study, two grape varieties, Merlot (Mer), and Malbec (Mal) were cofermented. On the second year, a third varietal, Petite Sirah (PS) was also studied. Cofermented wines containing every possible binomial combination of the varietals was made and one …

The Effects Of Cofermentation Of Cider And Apple Pomace On Cider Attributes, Abigail D. Affonso

Master's Theses

Phenolics are critical to the sensory attributes and health benefits of hard cider due to their contribution to the flavor, mouthfeel, and antioxidant activity. With the increase in demand for cider, the use of dessert apple varieties has become more common leaving ciders lacking in phenolics. However, a promising method to increase their phenolic content is through maceration with apple pomace. This study evaluated the effect maceration with apple pomace during cider fermentation on the extraction of phenolic compounds, as well as its effect on the sensory properties of the final product. For this study, ciders were fermented with 0% …

Effect Of Vine Age And Selected Winemaking Techniques On The Sensory Profile Of Central Coast Red Wines, Isabelle Lomonaco

Master's Theses

Descriptive sensory analysis is essential to understanding how differing varietals, viticultural techniques, enological techniques, vintage, regions, etc. impact the sensory characteristics found in wines. These studies analyzed the sensory impacts of vine age, whole cluster and stem addition influences, the frequency of cap management regimes, and selected fermentation variables, on 2019 Zinfandel, 2020 Syrah, 2020 Tannat, 2020 Cabernet Sauvignon, and 2021 Graciano wines respectively, from the Central Coast of California, USA. The investigation of Old vine Zinfandel indicated that these wines were defined as complex due to the wide variety of descriptors used to characterize them, having high color saturation …

Fate Of Listeria Monocytogenes On Two Salad Blends At Ideal And Abusive Temperatures, Taran Virdi

Master's Theses

The consumption of ready-to-eat (RTE) foods has increased with popular RTE salad blends including non-traditional ingredients such as shredded Brussels sprouts, kale, red and green cabbage, chicory, and broccoli stalk. Concurrently, there has been an increase in the number of foodborne illnesses and outbreaks associated with leafy greens. The potential risk associated with these ingredients must be addressed as they have not typically been consumed raw, especially since L. monocytogenes continues to be a leading cause of foodborne illnesses and outbreaks. This study evaluated the survival of L. monocytogenes on two RTE salad blends at refrigeration, mildly abusive, and abusive …

Value-Added Opportunities For Tomato And Peach Seeds, Valerie Michelle Lavenburg

Master's Theses

The food industry is increasingly concerned with operational sustainability and food waste reduction. In the United States, the tomato industry was worth $1 billion in 2020, and tomatoes are currently ranked second as the most consumed vegetable after potatoes. Tomato processors have striven to valorize pomace by-products, which contain seeds with valuable compounds such as 45% fiber, 30% oil, and 26% protein. The U.S. peach industry, which was worth $599 million in 2017, is also looking for alternative ways to utilize their seeds, made up of 52% oil. Both tomato and peach seeds are rich in bioactive compounds such as …

Lytic Bacteriophages And Lactic Acid As Processing Aids Against Salmonella Spp. And Escherichia Coli O157:H7 On Marinated And Tenderized Pork Loins, Sherita Li

Master's Theses

Within the last decade, pork consumption has steadily increased and continues to be the most consumed meat globally. However, pathogenic bacterial strains resistant to antibiotics have also been increasingly found in pig farms, animals, and the environment. Bacterial food poisoning cases due to Salmonella spp. and Escherichia coli (E. coli) O157:H7 appear to be linked with a variety of pork products. The meat industry has recognized that research is needed to combat the multi-drug resistance in foodborne pathogens with alternative methods of control. This study evaluated the effects of both E. coli- and Salmonella-specific lytic bacteriophages and …

Insects As A Sustainable Food Ingredient – Utilization Of Carrot Pomace, Identification Of Early Adopters, And Evaluation Of Mealworm Acceptability, Dominic Rovai

Master's Theses

Insects have been proposed as a sustainable alternative to livestock to help feed the growing population. Edible insects such as mealworms require less land and resources and can utilize food by-products to grow. While insects are consumed by over 2 billion people worldwide, they are not widely accepted in developed countries like the United States because of their unfamiliarity and the perception of disgust associated with entomophagy. The objectives of this research are to 1) grow mealworms using carrot pomace and determine an optimum diet for growth and nutritional composition, 2) identify and classify early adopters of insects, and propose …

Development Of A Portable Low-Moisture Food Pasteurization Device Using Rf Heating, Eric Jason Ohata

Master's Theses

Bacterial presence in low-moisture foods such as flour, cereals, baby formula, and spices, have become a concern due to sanitizing challenges. The food industry currently focuses on wet food sanitation as opposed to low-moisture foods because of bacteria’s inability to reproduce in low water activity media. Traditionally, food processing RF heating pasteurizes in mass quantities while an equivalent consumer device does not exist the market today. A consumer product would help eliminate food waste by providing an easy way to sanitize food and extend shelf life. The Portable Food Pasteurization (PFP) project is an interdisciplinary project involving the Electrical Engineering, …

The Effects Of Wort Oxygenation Scenarios On Fermentation Performance, Volatile Flavor Compound Development, And Flavor Stability In High Gravity Brewing, Ben Jabson

Master's Theses

High gravity (HG) brewing has become the most used strategy for maximizing fermenter productivity in commercial brewing. While HG brewing has many benefits, the additional stress placed on the yeast due to the higher concentration of fermentable sugars in the wort can negatively impact fermentation performance and flavor compound formation. A proper dissolved oxygen (DO) level is vital to guarantee adequate yeast performance during HG fermentations. Dissolved oxygen is vital to yeast viability throughout the fermentation process, as yeast requires oxygen to synthesize vital cell membrane components needed for continued anaerobic growth and cell division. Previous research has demonstrated the …

Effect Of Simulated Storage And Distribution On Listeria Innocua Growth In Non-Traditional Salad Ingredients, Emma L. Sandquist

Master's Theses

The fresh-cut produce industry has seen expansive growth in recent years, to meet consumer demand ready-to-eat (RTE) salads have included the use of non-traditional ingredients. Uncommon ingredients include beet greens, kale, broccoli stalk, and Brussels sprouts, since these ingredients have not historically been consumed raw, potential food safety issues should be reassessed. Current processing technologies include produce washes that can reduce microbial levels but do not eradicate all populations. The lack of a kill step in produce processing emphasizes the need to minimize pathogen contamination during production and growth during a product’s shelf life. Listeria monocytogenes, a leading cause …

Maleic Anhydride Compatibilized Peach Waste As Filler In Polypropylene And High Density Polyethylene Biocomposites, Caralyn Wong, Stephanie Jung, Joongmin Shin, Ajay Kathuria

Master's Theses

It is estimated that roughly 103, 515 tons of peach waste is produced annually in the US. The majority of the waste is disposed of in landfills, which contributes to climate change as they release 93 million metric tons of CO₂ equivalent. Peach waste principally consists of remaining stone and seed after flesh removal. The agro-waste includes both cellulose and lignin, which can be utilized as a filler in plastic packaging to reduce carbon footprints and material cost. The objectives of this research are (1) to develop peach flour (PF)-filled biocomposites with a polyolefin matrix using maleic anhydride-g-high density …

Valorization Of Carrot Processing Waste, Alexandra M. Duval

Master's Theses

Commercial carrot processors produce up to 175,000 tons of carrot waste annually. Carrot Mash (CM) is the term referring to the waste by-product of peeled baby carrot processing. Transportation of carrot processing waste is expensive due to its high- water content (approx. 83-95%). High in bioactive compounds (carotenoids) and dietary fibers, it is expected that its conversion into a value-added by-product is of interest to the carrot processing industry. Hemicellulose-rich plant materials have proven to be a source of oligosaccharides, which are known for their beneficial prebiotic activity. The objectives of this research were to: 1) determine the effect of …

Inactivation Of Foodborne Pathogens During Cider Fermentation, In A Cider Model System And Commerical Cider, Kathryn K. Yamada

Master's Theses

Hard cider is an alcoholic drink made from fermented crushed fruit, typically apples. The popularity of this fermented alcoholic beverage has been on the rise within the last decade. Historically, hard cider has been deemed safe due to the presence of ethanol and the low pH. Although there is lack of scientific evidence to prove that hard cider will and can be safe from foodborne pathogens. Escherichia coli O157:H7, Salmonella spp., and Listeria monocytogenes are three predominate foodborne bacterial pathogens of concern in the food and beverage industry. Escherichia coli O157:H7 in particular has been associated with fresh produce and …

Evaluation Of Chilling Efficiency, Meat Tenderness, And Microbial Analysis Of Broiler Carcasses Using Sub-Zero Saline Solutions, Samira Viliani

Master's Theses

The poultry industry is seeking an advanced chilling system that can improve chilling efficiency, microbial safety, and water consumption without compromising meat quality. The objective of this study was to evaluate the effects of sub-zero saline chilling methods on chilling efficiency, breast fillet tenderness and microbial reduction of broiler carcasses. Following evisceration and rinsing, broiler carcasses were randomly assigned to one of three chilling solutions: 1) 0% salt or ice water control (0% NaCl/0.5^oC), 2) 3% salt (3% NaCl/-1.8^oC), and 3) 4% salt (4% NaCl/-2.41^oC) solutions. Broiler carcasses in sub-zero saline solutions reached the …

Saponin Removal From Quinoa By Abrasion Processing, Luke Lundberg

Master's Theses

Quinoa is coated with a thin layer of saponins, glycosylated triterpenoids, that produce a bitter flavor when consumed. The average saponin content in commercial varietals from Bolivia average around 2.7% saponins and organoleptic testing shows the threshold for noticing a bitter flavor is below 0.12% (Medina-Meza et al., 2016). Current industrial processing methods use a combination of abrasion and turbulent water flow to remove saponin. This study will address the following research question: How will grain-to-grain and grain-to-surface abrasion affect the processing time to remove saponin from quinoa? In particular, can effective saponin removal be achieved in less than 10 …

The Effect Of Alcohol And Bitterness Levels On Brewing Yeast Viability, Nichole Elizabeth Bryant

Master's Theses

Two of the most popular beer styles within the craft brewing industry are India Pale Ales (IPA’s) and those with high alcohol by volume (ABV). Production of these styles requires high gravity fermentation and high amounts of bittering hops in order to reach the required values for ABV and International Bitterness units (IBU) respectively. The aim of this study was to determine the impact of high gravity fermentation and high IBU levels on yeast viability and repitching cycles.

An initial experiment on high gravity fermentations was done in order to assess the effects this variable had alone. Successive five day …

The Cal Poly Basic Needs Task Force Report - Fall 2018, Aydin Nazmi

Food Science and Nutrition

No abstract provided.

Parental Perspective And Feeding Practices Effects On Food Neophobia In Elementary-Age School Children, Farnoosh Ayoughi

Master's Theses

The Food neophobia (FN) behaviors in children are developed during childhood and can be influenced by parental FN and feeding behaviors. The objective of this study was to evaluate the relationship between FN and fruit and vegetable neophobia (FVN) among parents, the parents-reports on child's behavior and child self-reports. The effect of parental feeding practices and demographic variables on children’s FN and FVN were evaluated. Sixty-eight parents paired with their elementary school children (aged 7-12 years) in San Luis Coastal Unified School District participated in this study. Results indicated that parents reported their children more neophobic than children self-reported neophobia; …

Modifying The Mineral Profile Of Crickets (Acheta Domesticus) Using A Supplemented Diet, Rhianne Morgan Le Maxwell

Master's Theses

Captive insectivores may consume invertebrates as all, or part of their overall diet. The challenge with feeding captive insectivores involves the limited number of invertebrate species that are commercially available, and the lack of key nutrients provided by these insects. Among these insects, a naturally occurring low concentration of calcium and an inverse calcium to phosphorus ratio may put insectivores at the risk of developing hypocalcemia. A strategy to correct this nutrient imbalance involves supplementing the insect diet with high concentrations of targeted nutrients – a term referred to as gut-loading. Current industry guidelines recommend feeding a supplemented diet for …

The Effect Of Destoning And Enzymatic Pretreatments On The Biofuel Production From Olive Cake, Patrick Tai

Master's Theses

More than 16,000 tons of olive cake was produced in the United States in 2017. Olive cake is a by-product of olive oil extraction, which has limited animal feed potential, and poses an environmental threat when landfilled due to its high organic load and polyphenol content. This residue has potential for biofuel (bioethanol and biomethane) production because it is rich in polysaccharides such as pectin, hemicellulose, and cellulose. Yet, olive cake contains olive stones that can impede its conversion to biofuel. Therefore, two methods of destoning, centrifugation and screening by horizontal screw press, were first compared. Both methods removed an …

Strategies For Increasing The Release Of Pigments In Red Wine, Briana Heywood

Master's Theses

The perception of wine’s quality is directly influenced by its color. Anthocyanin molecules are responsible for imparting color to red wines. They are extracted from grape skins during alcoholic fermentation. This work compares the effects of three parameters: berry integrity, enzyme addition, and fermentation temperature, on phenolic compound extraction (total phenol, tannin and anthocyanin) during the production of Paso Robles’ Cabernet Sauvignon wine. Analyses on phenolic compounds were completed during alcoholic fermentation and barrel aging over the course of eighteen months. Berry integrity compared the degree of berry crushing (whole destemmed berries versus fully crushed berries). Results showed that phenolic …