Food Science Commons^™

Analysis Of Volatile Compounds And Their Changes During Liquor Aging Of Chinese Liquor 'Gujing Gongjiu', Qingchuan Liu

All Theses

Chinese liquor 'Gujing Gongjiu' is a traditional Chinese distilled alcoholic beverage that is categorized into a strong-aromatic fragrance liquor. It has a strong mixed floral, fruity, and sweet flavor with a smooth taste. Volatile compounds were extracted by headspace solid-phase microextraction (HS-SPME) from Gujing liquors that were aged for 1, 5, 10, and 20 years. Optimization of HS-SPME method was performed to determine the best experimental condition for extraction of liquor volatiles. Gas chromatography-mass spectrometry (GC-MS) was used for quantitative and qualitative analysis of liquor volatiles. Volatile compounds were identified by Kovat's retention indices and their mass spectrum. The influence …

Effect Of Low And High Molecular Weights Water Soluble Chitosan On Oxidation Of Whole Milk Powder, Wesam Al-Jeddawi

All Theses

Autoxidation significantly decreases the shelf life of whole milk powder due to primary and secondary oxidation products such as hydroperoxides, aldehydes, ketones, alcohols and hydrocarbons. Water soluble chitosan has been shown to reduce oxidation by chelating metals or combining with lipids resulting in a significant antioxidative effect. The objective of this study was to determine the antioxidative effects of different concentrations of low (L) and high (H) molecular weight water soluble chitosan (9 and 90 kDa, respectively) on whole milk powder (WMP). Commercially dried WMP was obtained and rehydrated 50% (wt/wt) with various aqueous chitosan solutions (2% L2, 4% L4, …

Effect Of Bromelain On Duck Breast Meat Tenderization, Ahmet Buyukyavuz

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ABSTRACT This study was conducted to determine the effect of bromelain on duck breast meat tenderization. Duck breasts were marinated with different concentrations (0, 1.5, 3 and 4.5%; C2, B1.5, B3 and B4.5, respectively) of bromelain and a solution composed of 92% refrigerated water, 6% salt and 2% sodium tripolyphosphate by using a vacuum food tumbler machine. A second non-marinated control (C1) was also included. Marination tumbling was operated at 8 RPM for 8 minutes. Physico-chemical and quality parameters were determined on raw and cooked samples. A significant reduction (p<0.05) in pH was observed in all bromelain treated samples when compared to C2. Although there was a significant reduction in pH of B1.5 when compared to C1, there was no significant difference among B3, B4.5 and C1. A significant increase was observed in water holding capacity of B3 and B4.5 when compared to C1. While a significant reduction was observed in lightness (L*), no differences were observed in redness (a*) and yellowness (b*) values of marinated samples (C2, B1.5, B3 and B4.5) when compared to C1. However, a significant increase in lightness (L*), and a significant decrease in redness (a*) and yellowness (b*) were observed in cooked bromelain treated samples. No differences were observed in razor shear forces, moisture content and water activity between treatments. There was no significant difference in cook yield of all marinated samples (C2, B1.5, B3, and B4) when compared to the C1. A significant reduction (p<0.05) in Warner-Bratzler shear force values was observed in all marinated samples when compared to untreated control (C1). Based on results, use of bromelain in marination solutions under the conditions tested here would not be cost effective.

Comparison Of Simultaneous Distillation And Extraction (Sde) And Headspace Solid Phase Microextraction (Spme) For Determination Of Volatiles Of Muscadine Grapes (Vitis Rotundifolia), Pei-Ching Lin

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Vitis rotundifolia also called 'Muscadine' grows abundantly throughout the southeastern United States. Muscadine grapes have desirable flavors, making them suitable to be either consumed as fresh fruit or made into wine and jam. Moreover, muscadine grapes have been reported containing rich complex phytochemicals, including anthocyanins and polyphenols that possess antioxidant, anti-cancer, anti-inflammatory and antimicrobial activities. Therefore, muscadine grapes have become increasingly popular in recent years due to its unique aroma, as well as health benefits. Various volatile compounds contribute to the aromatic flavors of muscadine grapes. In regards of their low concentrations, conventional simultaneous distillation and extraction (SDE) and solid …

A Study Of The Frothing Capacity Of Whole Milk- 1. A Market Survey Of Conventional And Organic Milks, 2. The Effect Of Clean In Place (Cip) Cleaning Solutions, Sara Stancil

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Gourmet coffee drink consumption is on the rise (NCAUSA 2013). With most of these coffee drinks including milk and/or milk foam, an emphasis on producing quality foam is of high importance. Recent complaints have been received on the failure of milk to foam to expectations of the coffee house (Randolph & Associates 2013). Identifying the source of this failure could enable the milk industry to provide higher foam quality milk to meet the growing needs of coffee houses.

A two-part study on the frothing capacity of milk was carried out to investigate potential variations in the market place and to …

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 …

Influence Of Compost Particle Size On Pathogen Survival Under Greenhouse Condition, Junshu Diao

All Theses

The number of foodborne pathogen outbreaks related to fresh produce has increased significantly in recent decades. Animal waste directly applied to agricultural field is one of the possible contamination sources for fresh produce. Composting is one of the recommended means for waste treatments to eliminate or reduce pathogens in manure on farms. Although pathogens can be eliminated by proper composting process, pathogens are able to survive, recolonize and regrow on compost heap surfaces under certain conditions. Due to the outdoor nature of composting process, bioaerosols with different particle sizes can be generated on compost surfaces which can carry pathogens, travel …

Bacterial Recovery, Transfer To Hands And Survival On Restaurant Menus, Ibtehal Alsallaiy

All Theses

Some non-food contact surfaces such as restaurant menus are not routinely cleaned or evaluated for microbial contamination and thus may be a potential contamination risk. The main objectives of this study were to detect bacteria on restaurant menus, test the rate of bacteria transfer from menus to consumers and determine the survival rate of bacteria on the menu surface. Evaluation of samples can 'find' that menus harbored detectable levels of aerobic organisms and Staphylococcus spp. The average mean of Total Plate count (TPC) was 28 CFU/15cm2 per sampling area during busy periods and 15 CFU/15cm2 per sampling area during less …

Procuring And Tracing Produce From Small- And Medium- Scale Farmers For Use In Institutional Foodservice Operations In Nc, Sc And Ga, Anita Nunnelley

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In response to concerns about an increasingly globalized food system in the United States, and increasing interest in the connections between small- and medium-scale (SMS) farms and institutional foodservice operations (IFO), the U.S. has recently developed legislation to link farmers to institutional markets (Joshi, Azuma, & Feenstra, 2008; Poulton, Dorward, & Kydd, 2010; USDA, 2010; Wootan, 2012). The purpose of this study is to determine if these connections are viable, sustainable and ultimately if the food is safe for consumption in the IFO. There are significant logistical, contractual and food safety concerns when sourcing food for IFOs from SMS farms. …

Effect Of Temperature On Sensing Intensity Of Basic Tastes: Sweet, Salty And Sour, Keri Lipscomb

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Twenty semi-trained subjects determined the effect of temperature on basic tastes sweet, salty and sour. The sensory evaluations were performed on each basic taste and on various combinations of the three tastes at serving temperatures 3, 23 and 60¡C. A single intensity level was used for all sensory evaluations and 3 replications of each panel were performed. Results from the panels provided some evidence of temperature affect, both when evaluated singularly and in combination.
The perceived intensity of some sweet and sour samples was affected by a change in temperature. Sensing intensity of the salty samples was not significantly affected …

Factors Affecting The Production Of Concentrated Blue Cheese Flavorings, Jason Raines

All Theses

The effects of media type and culture selection on the aroma profile of Blue cheese flavorings produced using submerged culture fermentation were studied. Fermentations were carried out for 16 hours then compared using sensory analysis and GC/MS SPME. The differences between samples were minimal. Samples produced with adjunct media were found to have higher concentrations of methyl ketones and more &ldquo'creamy'&rdquo aroma character than samples produced from standard media. Higher levels of free fatty acids were found in standard media samples. Adjunct cultures appear to enhance the &ldquo'creamy'&rdquo character of Blue cheese flavorings.
Near-critical and supercritical carbon dioxide were used …

Assessment Of Viability Of Probiotic Bacteria In Non Dairy Food Matrices Under Refrigeration Storage, Muthu Dharmasena

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Functional foods serve nutrients and physiologically active components for a healthy living. In most countries, the products related to having a healthy gut dominate the functional foods market. These products are prebiotics, probiotics and synbiotics. Concerning the health benefits, various probiotics are introduced to food matrices. Though dairy is the ideal food matrix for probiotics, the trend of non-dairy probiotics is growing among consumers.
This study included two research objectives: surveying the commercial probiotic containing products for probiotic level and developing a practical home-made probiotic fermentation process. The first part of this study was mainly based on assessing viability of …

Developing Value-Added Peptide Antioxidants From Rendering Products, Xiaoting Xing

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Synthetic antioxidants, such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), Vitamin E and ethoxyquin, have been commonly added to formulated animal feeds in order to delay discoloration and deterioration due to oxidation. However, these synthetic antioxidants have been limited in their applications as food additives because of potential health hazards. Specifically, synthetic antioxidants have been considered to be linked to various forms of cancer, most commonly kidney, liver and bladder cancer. In this work, value-added peptide antioxidants from rendering products were developed for use in potential aquaculture and pet food markets as natural antioxidant substitutes for synthetic antioxidants. The antioxidant …

Analysis Of The Relationship Between Sweetener Properties And Variations In Both Functionality And Final Product Characteristics, Danielle Lynn

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Scientific research and media attention regarding possible health concerns related to high fructose corn syrup (HFCS) consumption has led to a negative consumer perception of this ingredient. Therefore, the baking industry, which commonly uses HFCS as a sweetener, needs to identify appropriate replacements. Even though invert sugar (IS) is nutritionally similar to HFCS, its use in product formulations would allow HFCS to be removed from ingredient lists. Light agave nectar (LA) and amber agave nectar (AA) are two potential replacement ingredients, with the added benefit of low glycemic indexes for products targeting the diabetic community. This study was designed to …

Effects Of Soy Supplementation On Bone Characteristics And Egg Quality In Peak Production Laying Hens, Kealani Izquierdo

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In the last few decades equol, a metabolite of the isoflavone daidzein, has become the target of various animal and human studies. Coined the key to health benefits associated with soy foods, equol formation been implicated in the healthy profiles associated with Asian populations. As a metabolite of daidzein, equol must be synthesized from its precursor by intestinal bacteria; however, clinical and epidemiological studies indicate that only about a third of the general human population possess the microflora necessary to metabolize equol. Research indicates that by supplementing laying hens with soybean meal, equol deposition into table eggs can be stimulated, …

Extraction And Identification Of Volatile Constituents Of Oplopanax Horridus , Gregory Jones

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O. horridus is an important medicinal and spiritual plant for native peoples where it natively grows. Secondary volatile metabolites which compose the essential oil were isolated by atmospheric simultaneous distillation-solvent extraction (SDE) and headspace solid phase microextraction (HS-SPME) from the bark and leaves of Oplopanax horridus. The differences between the two extraction methods was investigated for their sensitivity, precision and use in separating volatile compounds from sample matrices.The extracts were analyzed by capillary gas chromatography with mass spectrometric detection. Compounds were identified according to their non-isothermal Kovats indexes, mass spectra, or by comparison with analytical standard substances. The bark essential …

Use Of The Health Belief Model To Assess Hand Hygiene Knowledge, Perceptions, And Practices Of Saudi Students Studying In The U.S., Najla Khateeb

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Many factors influence hygiene but those that have the greatest impact vary widely across population groups. Our aim was to characterize hand hygiene practices of Saudi students studying in the U.S. by completing two objectives: (1) assess hand hygiene knowledge, perceptions, and practices of Saudi students studying in the U.S. and (2) determine the relationship among knowledge, perceptions, and practices.
A modified version of the Health Belief Model was the theoretical framework to characterize hand hygiene practices. A web-based instrument was posted to the ¬DSaudis Studying in USAÁÂ Facebook page. The instrument was prepared in English then translated into Arabic. …

Thermal Destruction Of Geobacillus Stearothermophilus In Rendered Animal Co-Products, Yubo Zhang

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The non-pathogenic, heat stabile organism Geobacillus stearothermophilus was used during thermal death time testing of rendered poultry materials from three different rendering plants. G. stearothermophilus is an endospore–forming, Gram positive, thermophilic bacterium that is commonly used in the canning industry. A modification of the method of Kim and Naylor (1966) was used to prepare a G. stearothermophilus spore suspension. Uninoculated and inoculated rendering samples containing 50% fat and rendered crax were prepared. Lecithin and 2,3,5–triphenyl–2H–tetrazolium chloride (TTC) were used during sample enumeration to emulsify the high fat samples and to aid in detection of colonies, respectively. Commercial rendering cookers are …

Shelf Life Studies On Processed Peaches, Divija Unhale

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A series of experiments were conducted on the preservation of fresh peaches using freezing and heat (hot-filled packaging). In the first experiment, the effects of four calcium salts (calcium chloride, calcium lactate, calcium citrate, calcium phosphate) on the texture of processed peach slices were determined. Peach slices were immersed in solutions containing dissolved calcium salts at levels of 0.5, 1 and 2 % for 1 minute then stored at 4 ¡C for 3 days. Treatments with calcium salts were firmer than non calcium treated peach slices at all levels. Calcium lactate at 2 % level was best in terms of …

Chemical Composition And Antioxidant Properties Of Maya Nut (Brosimum Alicastrum), Hatice Kubra Tokpunar

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ABSTRACT
Maya nut was investigated in term of its moisture, ash content, antioxidant activities, phenolic components by high pressure liquid chromatography-ultraviolet detector (HPLC-UV) and fatty acid composition by gas chromatography-flame ionization detector (GC-FID). The results showed that Maya nut was mainly composed of 55.06% linoleic acid (C18:2 n6), 27.2% palmitic acid (C16:0), 6.26% stearic acid (C18:0), 9.9% linolenic acid (C18:3 n3), and 3.36% Cis-11-Eicosenoic (C20:1). Maya nut possesses a higher content of polyunsaturated fatty acids (PUFAs) (linoleic and linolenic acid), but lower content of monounsaturated fatty acids (MUFAs) than canola oil and olive oil. The antioxidant capacities and total phenolic …