Food Science Commons^™

Modeling For Thermal Resistance Of Non-O157 Shiga Toxin Producing Escherichia Coli In Ground Beef, Jagpinder S. Brar

Open Access Dissertations

Predictive models in microbiology are used for estimating the growth or survival of microorganism in a set of environmental conditions. A validated predictive model provides an alternative to extensive survival and shelf life studies. In this study, a predictive inactivation model for non-O157 shiga toxin producing Escherichia coli (STEC) in ground beef was developed. Six strains of non-O157 STEC; E. coli O26:H1, E. coli O45:H2, E. coli O103:H2, E. coli O111:H8, E. coli O121:H9, and E. coli O145: nonmotile, has similar pathogenicity as E. coli O157:H7 and can cause serious food borne illnesses. These pathogens are considered as an adulterant …

The Role Of Nutrition Education And Active Choice To Increase Fruit And Vegetable Consumption Among Second Grade Students During Lunchtime, Robyn M. Cafiero

Theses, Dissertations and Culminating Projects

Fruit and vegetable intake within the United States is considerably lower than the standards set by the United States Department of Agriculture. With this information, there is no surprise that these rates are especially low for school aged children. Although many studies have tried to incorporate programs that would effectively increase the consumption of fruits and vegetables among youngsters, many have fallen short with being able to sustain consumption over time. This study provided a way to increase fruit and vegetable consumption during lunchtime for second grade students by using a dual module of the Social Cognitive Theory and active …

Edible Insects As A Source Of Food Allergens, Lee Palmer

Department of Food Science and Technology: Dissertations, Theses, and Student Research

Increasing global population increasingly limited by resources has spurred interest in novel food sources. Insects may be an alternative food source in the near future, but consideration of insects as a food requires scrutiny due to risk of allergens. Currently, the insect Dactylopius coccus, known as cochineal, is used to produce carmine, a natural red pigment used in food, which has caused allergic reactions. This study investigated allergens of cochineal focusing on purification from the pigment. Mass spectrometry identified a previously described major allergen of cochineal and a tropomyosin, although further work is required.

Tropomyosin is a major cross-reactive allergen …

Formation Of Bioactive-Carrier Hollow Solid Lipid Micro- And Nanoparticles, Junsi Yang

Department of Food Science and Technology: Dissertations, Theses, and Student Research

In recent years, bioactive lipids (e.g., carotenoids, phytosterols, and tocopherols) have attracted a lot of interest to develop health and wellness promoting foods and beverages. However, bioactive lipids are water-insoluble and degrade easily during processing and storage, making their addition into foods and beverages challenging.

The main objective of this thesis was to develop a novel green process to form bioactive lipid-carrier hollow solid lipid micro- and nanoparticles using supercritical carbon dioxide (SC-CO₂). Specific objectives were to develop hollow solid lipid micro- and nanoparticles using SC-CO₂ technology, and to load the hollow solid lipid micro- and nanoparticles …

A Bifunctional Nanocomposites Based Electrochemical Biosensor For In-Field Detection Of Pathogenic Bacteria In Food, Meng Xu

Graduate Theses and Dissertations

This research focused on the application of electrochemical biosensors for the rapid detection of pathogenic bacteria, Escherichia coli O157:H7 and Salmonella Typhimurium, in foods. The possible presence of pathogenic bacteria in foods has always been a great threat to the wellbeing of people and the revenue of food companies. Therefore, the demand for rapid and sensitive methods to detect foodborne pathogens is growing. In this research, an impedimetric immunosensor was first developed for the rapid detection of E. coli O157:H7 and S. Typhimurium in foods. It was based on the techniques of immunomagnetic separation, enzyme labelling, and electrochemical impedance spectroscopy …

A Portable And Automatic Biosensing Instrument For Detection Of Foodborne Pathogenic Bacteria In Food Samples, Zhuo Zhao

Graduate Theses and Dissertations

Foodborne diseases are a growing public health problem. In recent years, many rapid detection methods have been reported, but most of them are still in lab research and not practical for use in the field. In this study, a portable and automatic biosensing instrument was designed and constructed for separation and detection of target pathogens in food samples using nanobead-based magnetic separation and quantum dots (QDs)-labeled fluorescence measurement. The instrument consisted of a laptop with LabVIEW software, a data acquisition card (DAQ), a fluorescent detector, micro-pumps, stepper motors, and 3D printed tube holders. First, a sample in a syringe was …

Risk Assessment And Research Synthesis Methodologies In Food Safety: Two Effective Tools To Provide Scientific Evidence Into The Decision Making Process, Juan E. Ortuzar

Department of Food Science and Technology: Dissertations, Theses, and Student Research

The food supply chain is a complex and diverse system. Some food products need minimum processing to reach the consumers, while others involve several different processes, countries and suppliers, can take several months to be on the table of the end consumer. Regarding food safety, the public health of consumers is at stake and the consequences of outbreaks could prove disastrous. This has been recognized as a matter of global importance for the food industry and authorities around the world since several efforts to improve quality, safety and trade of food have arisen since the early 1960s. The birth of …

Impact Of Microwave-Assisted Heating And Enzymatic Treatment On Functional And Antioxidant Properties Of Rainbow Trout (Oncorhynchus Mykiss) By-Product Hydrolysates, Elizabeth Bich Hang Nguyen

Open Access Theses

Fish protein hydrolysates (FPH) have been widely used as a mean to better utilize fishery by-products through the use of proteolytic enzymes to produce a wide range of functional peptides that can be used as food ingredients. Studies have shown that these functional peptides have enhanced interface-stabilizing properties (e.g. functionality) and antioxidant activity. FPH production can be accelerated by using rapid heating methods (e.g. microwave) compared to slower conventional heating (CH). The objective of this study was to investigate the effects of microwave heating (MW) during enzymatic hydrolysis on functionality and antioxidant properties of FPH. Treatments consisted of adding Alcalase™ …

Effects Of Fermentation By Yeast And Amylolytic Lactic Acid Bacteria On Grain Sorghum Protein Content And Digestibility, Christina Day

Graduate Theses and Dissertations

Grain sorghum is an underutilized crop despite many advantages to its cultivation. A drought-tolerant plant with many pest-resistant cultivars, its applications are limited by problems with nutrient availability, particularly protein digestibility. Digestibility of grain sorghum protein is reduced by antinutritional compounds in the grain like tannins and phytates, and by moist-heat cooking. Some of these concerns can be mitigated by how the grain is processed. Fermentation is one processing method that can improve digestibility. Fermentation can also concentrate protein in a substrate. In this experiment, grain sorghum was subjected to different treatments and used as a substrate for yeast fermentation. …

Antimicrobial Inhibitory Activities Of Phenolic Extracts From Four Selected Soybean Hulls In Culture And Chicken Skin Model Systems, And Preliminary Ace-Inhibitory Activity, Rajaa Abdulkair Abutheraa

Graduate Theses and Dissertations

Soybean components provide health benefits to humans. Soybean hulls, a major by-product of the soybean processing industry consist of complex carbohydrates, proteins, lipids and polyphenols such as anthocyanidins, proanthocyanidins and isoflavones. The polyphenolic compounds in the hulls give them various colors such as black, brown, green, yellow or even a mottled appearance. Studies have reported different soybean varieties with varying total phenolic compounds in their seed hulls, which have antioxidant property. Phenolic extracts can be used as substitutes for synthetic antimicrobials and preservatives to assist in preventing the growth of pathogens such as Salmonella Typhimurium, E coli 0157:H7, and Campylobacter …

The Effects Of Using Cinnamon Leaf And Bark Essential Oils On Listeria Monocytogenes (L.M.), Salmonella Typhimurium (S.T.), In Model System, Strawberry Shake And Fresh Celery, And Sensory & Shelf Life Studies, Wafaa Brnawi

Graduate Theses and Dissertations

Essential oils derived from the bark and leaves of the cinnamon plant have long been used as natural preservatives and flavoring agents in different types of foods. In this study, we evaluated the antimicrobial effects of cinnamon essential oils (CEOs), obtained from cinnamon leaf or bark, against two foodborne pathogens i.e., Salmonella Typhimurium (S.T.) and Listeria monocytogenes (L.m.). Two different concentrations of microbial loading were used i.e.,109 and 104, cultured in nutrient media broth, strawberry shakes, and on celery sticks. Both CEOs of leaf and bark at 0.5% and 1% were found to completely inhibit S.T. and L.m., immediately after …

Effects Of Harvest Conditions And Thickness Fractionation On Physicochemical Properties, Cooking And Sensory Characteristics Of Long Grain Rice, Sara Esther Jarma Arroyo

Graduate Theses and Dissertations

Previous research has demonstrated the extensive impacts of various environmental and processing conditions on rice milling and processing characteristics. Nevertheless, little is known about the influences of these conditions on cooking and sensory qualities of rice. The present study aimed to determine the impact of cultivating location, harvest moisture content (HMC), and thickness fractionation on the physicochemical properties, and cooking and sensory characteristics of long-grain rice. Four long-grain rice cultivars (purelines: Cheniere and V3501, and hybrids: XP760 and XL753) were cultivated at Harrisburg, AR and Alvin, TX, and harvested at three HMC. Rough rice lots were conditioned and a portion …

Effects Of Glycosidase（R.B1l And R.Cl） On Configuration Of Isoflavones And Improvement Of Flavor In Soybean Milk, Zhou Weijie, Xia Rong, Zhu Chongyang, Pei Jing, Tao Huiyuan, Cheng Yongqiang

Food and Machinery

In order to obtain a higher content of soybean isoflavone glycosides and improve the flavor of soybean milk, two kinds of glycosidase (R.B1L and R.CL) were used in soybean milk processing, then the soybean isoflavones and lavor compounds were detected by high performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry technique(GC/MS) respectively. The results showed that the amount of soybean isoflavone aglycones increased 7.289 μg/g, which was 35.7% higher than the control group. While, the bean flavor compounds of hexanal and 2-amyl furan decreased 10.8%, and the aroma compounds of hexyl alcohol and anti-2-nonene aldehyde increased 10.88%. It indicates that …

The Inhibitory Effect On Tyrosinase From P-Coumaric Acid, Ferulic Acid And Feruloylated Oligosaccharides, Yi Jingjing, Ou Shiyi, Dong Yingyan, Chen Qiuming

Food and Machinery

This study investigated the inhibitory effects of p-coumaric acid, ferulic acid and feruloylated oligosaccharides on catalytic activities of tyrosinase by analysising tyrosinase steady state activity and enzyme kinetics. The results showed that the three compounds were found to efficiently inhibit tyrosinase monophenolase activities. The p-Coumaric acid was the strongest inhibitor followed by feruloylated oligosaccharides and ferulic acid, with the IC₅₀ value of 0.75, 3.20, 9.30 mmol/L respectively. Moreover, p-coumaric acid and ferulic acid were found to inhibit the activities of diphenolase with IC₅₀ value of 4.3, 12.7 mmol/L respectively; however, feruloylated oligosaccharides showed no inhibitory effect on diphenolase …

Optimization Of A Microplate Bioassay Method Of Filtering Alpha-Glucosidase Inhibitors, Wang Hongyue, Chen Zhong, Jian Xufeng

Food and Machinery

The half inhibitory concentration (IC₅₀) of alpha glucosidase inhibitors was detected based on a microplate assay method in this study in order to find the effective inhibitors for preparing hypoglycemic functional food. The reaction conditions were optimized by the four aspects, i.e., the enzyme concentration, the detection wavelength, the substrate concentration and the reaction time. The results showed that the optimum enzyme concentration ranged from 2.0 mg/mL to 3.0 mg/mL, and waves 520 nm and 492 nm were optimum among the five waves, 405, 450, 492, 520, 630 nm. Moreover, the suitable substrate concentration of sucrose ranged from …

Separation, Screening And Identification Of Special Microbial Strain For Beef Meat Tenderizer, Tan Ya, Li Zongjun, Li Ke, Wu Genliang

Food and Machinery

In order to obtain microbial strain suitable for the tenderization of beef, a total of 22 bacteria of producing proteinase were isolated from traditional lobster sauce and wine song in Guizhou. With the screening by using microscopy, analyses of enzyme activities, and TPA value of beef with in treatment of fermented broth, a bacteria defined as D7 was found the optimal strain, and its enzyme activity was 71.68 U/g. The molecular biological identification results showed that it was very similar to Bacillus amyloliquefaciens (JN700123.1), and the similarity was 99%, on the basis of molecular biology identification, using 16S rDNA sequences …

Identification Of 81 Pseudomonas Aeruginosa By Phylogenetic Analysis Of 16s Rrna Gene Sequence, Zeng Xiaocong, Zhou Lu, Su Miaozhen, Han Zhijie, Chen Danxia

Food and Machinery

81 Pseudomonas aeruginosa from Guangdong Provincial Institute of Food Inspection were identified by 16S rRNA sequence analysis. The DNA was isolated and the sequences of 16S rRNA gene were amplified by PCR with the bacterium universal primers, and then the PCR products were sequenced after 2% agarose gel electrophoresis. Moreover, the corrected sequences were aligned with Clustal X and the phylogenetic tree was constructed by MEGA5.1. Consequently, the identified results of the 81 strains confirmed their original identification before. On the phylogenetic tree, No. 24-3-QY strain formed a separate branch with No. 100-5-JM strain and No. 106-3-JM strain. No.2 8-1-DW …

Effect Of Gastrodia Elata Bl. Extracts On The Biosynthesis Of Extracellular Proteins In The Grifola Frondosa Under Submerged Fermentation, Huang Zhong, Wu Tianxiang, Yang Zutao, Zhu Sijie

Food and Machinery

Gastrodia elata Bl. extracts was added into the system of Grifola frondosa submerged fermentation, and then supplement-ation of Gastrodia elata Bl. extracts were optimized according to the biomass and the synthetic quality of extracellular proteins in G. frondosa. The changes of components in G. elata Bl. extracts before and after the sterilization, including gastrodin, p-hydroxybenzyl alcohol, p-hydroxybenzaldehyde, and parishin, were analyzed using HPLC. Moreover, the relationship of this changes between G. elata Bl. extracts and the in G. frondosa fermentation system were also investigated. The results revealed that 7% (v/v) G. elata Bl. extracts could facilitate G. frondosa to grow …

Identification And Quantitative Analysis Of Soybean Milk And Rice Milk In Raw Milk, Fang Xuanqi, Yang Daiming, Liu Lansong, Zhou Binbin, Zhang Juan, Zhang Jihong

Food and Machinery

In order to identify raw milk, nonlinear chemical fingerprint of raw milk from different areas and that mixed with different content of soybean milk or rice water was established based on the steady system of “sodium bromate + manganese sulfate + Sulfate + acetone” by using nonlinear fingerprint technique . The raw milk samples that incorporated with soybean milk or rice water could be identified, and the adulterant could be judged by the characteristic information of their nonlinear chemical fingerprint. According to the relationship of parameter information and adulterant content, the relative global content of soybean milk or rice water …

Determination Of Vanillin And Ethyl-Vanillin In Milk Powder By Gas Chromatography-Mass Spectrometry, Zheng Xuan, Huang Jin, Lin Jie, Li Ju, Wei Xiaoqun, Cai Chun, Chen Yanfen, Feng Jieli, Guo Qingyuan

Food and Machinery

A method for determination of vanillin and ethyl-vanillin in milk powder was established by auto headspace solid-phase micro-extraction coupled with gas chromatography-mass spectrometry (GC—MS), and the influence factor were also studied, such as solid phase micro-extraction head, time and temperature of adsorption and desorption. As a result, the limits of determination (LOD) of vanillin and ethyl-vanillin were 0.5 mg/kg. The spiked recovery was between 90.0% and 100%, and the RSD ranged from 1.9%～4.1%(n＝6). This method could eliminate the interference of complicated matrix, conveniently, quickly and exactly, which was applicable for quick determination of vanillin and ethyl-vanillin content in milk powder.

Determination Of Five Kinds Of Clove Phenol Anesthetic In Aquatic Product By Hplc With Molecularity Imprinted Solid Phase Extraction, He Hongjian, Huang He, Gao Ping, Liu Ya, Jiang Zhihong, Cao Zhanhui

Food and Machinery

A new method of molecularly imprinted solid phase extraction (MISPE) combined with high performance liquid chromatography (HPLC) was developed for detecting five kinds of clove phenol anesthetic in aquatic product. Using eugenol as template molecule, methacrylic acid as functional monomer, ethylene glycol dimethacrylate as cross linking agent, molecularly imprinted polymers were synthesized by bulk polymerization and made into extraction column. Through the response surface analysis template molecule and functional monomer, crosslinking agent the best proportion was 1∶4. 55∶23. 21, and the recovery rate of these compounds reached 90% by using methanol as solvent and acetic acid solution as eluent. The …

On-Line Determination Of Emergency Pollution Of 3-Nitropropionic Acid In Drinking Water By Flow Injection Chemiluminescence, Zhang Xuhui, Tang Shuze, Deng Xiaoling, Zhu Yao, Wu Shizheng

Food and Machinery

On the basis of inhibition of chemiluminescence reaction of luminol and potassium permanganate in sodium hydroxide medium by 3-nitropropionic acid, a novel flow-injection chemiluminescence method for determination of 3-nitropropionic acid in drinking water was developed. A linear range for 3-nitropropionic acid determination was 1～150 mg/L. The detection limit of 3-nitropropionic acid was 0.28 mg/L and relative standard deviation (RSD) was 1.9%, with the recovery of 76.5%～93.8%. This online determination system showed a good accuracy and selectivity and has great potential application in rapid detection and alarm of emergency pollution of 3-nitropropionic acid in drinking water.

Design Of Mixing Reaction Tank Of Suitable For High Viscosity Non-Newtonian Fluidossein, Han Dong, Jia Wei, Zhang Chunhui

Food and Machinery

In order to solve the problems of the material of mixed unevenness, low dissolved efficiency, uncontrollable reaction temperature and aroma loss in the conventional mixing reaction tank, a kind of mixing reaction equipment was designed and developed for high viscosity non-Newtonian fluidossein. The mixing reaction equipment consisted of tanks, feeding apparatus, and devices of vertical composite stirring, bottom emulsification stirring and the reaction volatiles collected reflux. This equipment was well suited for high viscosity non-Newtonian fluid to blend, mix and react, and able to achieve multifunctional operation with energy saving. Moreover, it helped to increase the degree of controllability of …

Modeling And Dynamic Simulation Ofautomatic Apple Oriented Mechanism, Ma Yao, Yu Jinghu

Food and Machinery

It’s difficult to distinguish between apple damage and fruit axis and calyx in image processing. This results in poor efficiency and accuracy. An apple orientation mechanism is designed, and realized orientation of apple before image acquisition, thereby reducing image processing time. It mainly includes fruit pan, synchronous wheel, fixed caster and drive shaft. ADAMS was used to simulate the orientation process of apple, which verified the feasibility of the mechanism, and sure that the apple will not scratched in the orientation process. In order to improve the efficiency of apple sorting system, the optimal scheme was obtained by simulating the …

Tank Design And Parameter Optimization Of The Fruit Grain Liquid Storage, Yin Shuizhong, Huang Xiaohua, Yang Dizhou, Ding Zhihui, Zhu Can

Food and Machinery

A fruit grain beverage liquid mixing tank was designed in this study, including the structure of the cylinder block and the mixing paddle, and related parameters were provided. The numerical simulation was carried out by orthogonal test and FLUENT,to determine the influence degree of the factors, such as the installation height of the agitator, the diameter of the impeller and the rotation speed of the propeller, and the parameters of the stirred tank, were optimized to obtain the optimal parameter solution. Results: The main order of the factors that influenced the stability of the agitator concentration was as follows: the …

Design Of Extrusion-Grind Rubber Fruit Test Sheller, Fan Haiyan, Wang Tao, Wu Di, He Xiaofan

Food and Machinery

A test sheller for rubber fruit was designed and manufactured according to the principle of extrusion-grind, and it consisted of units of driving and extrusion-grind, the lectrical elements for realizing automatic clockwise and anti-clockwise running of motors, and the frame, etc. Adopting the principle of reciprocating friction and extrusion, the fruit shells were separated under the dual of friction and extrusion pressure. Our results showed that the device could perform well and was, easy to operate, especially, the hulling rate could reach 78.3% by using it. Thus this sheller could be utilized in researches on effects and the mechanism of …

Comparative Study Of The Failure Pressure Between Sealing Liquids And Gas With Magnetic Fluid, Wang Hujun, Li Decai, Zhen Shaobo, He Xinzhi, Wang Siqi

Food and Machinery

Magnetic fluid has been widely used in sealing gas, but sealing liquids with magnetic fluid is still in the research stage. In this paper, the effect of velocity difference on failure pressure was theoretically deduced. The magnetic fluid seal structure was designed and an experiment its rig was set up, and then the seal performances of sealing gas and liquids with magnetic fluid were studied. The results showed that the failure pressures of sealing liquids and gas statically under the same sealing gap were almost the same, and the failure pressure was generally not affected by the speed of the …

The Effects Of Condensing Temperature Changes On Plate Freezer With Two-Phase Ejector, Tian Xiaoyu, Wan Jinqing, Cao Xiaochen, Li Jianguo

Food and Machinery

The working performance of plate freezer with two-phase ejector in different condensing temperature was investigated in this study. Moreover, the effects of condensing temperature on freezing rate and total energy consumption of plate freezer was also studied. Then the entrainment coefficient in stable conditions and explores the effects on Jet pumps were analyzed by changing the condensing temperature. The results showed that when the condensing temperature was 25 ℃, the ejecting coefficient was the highest about 1.58. Compared with 40 ℃and 30 ℃, the energy consumption was lowered by about 3.3% and 10% at 25 ℃, and the freezing time …

Electromagnetic Vibration Quantitative Feeding System Based On Fuzzy Pid, Qi Jun, Gong Dawei, Li Yan, Yan Qingqun

Food and Machinery

To solve the problem of traditional electromagnetic quantitative feeding system in the process of the open loop control the feeding speed setting arbitrary large, not according to the intelligent control strategy for dynamic adjust the feeding speed, a quantitative electromagnetic vibration feeder was designed based on fuzzy PID control system. Taking the mechanical structure design of the system as a whole, the conduction angle of silicon controlled rectifier was obtained by theoretical analysis and mathematical relationship between amplitude, and according to this, the simplified mathematical model of electromagnetic vibration feeder second order was established. The simulation results show that the …

Optimal Design For Bidirectural Cramp Frame Based On Triz Theory, Du Chunkuan

Food and Machinery

It was well known that standard cramp frame can only clamp a group of workpieces, without the ability to catch many groups of workpieces with related position constraint. To solve this problem, a design solution based on TRIZ theory as well as an inventive principle were proposed in this study. A bidirectural cramp frame with hyperbolic structure was designed, and it could clamp workpieces on both sides. Therefore, the application range and fields of this new kind cramp frame were expanded. Moreover, the bidirectural cramp frame was also analyzed and optimized using the finite element method. Finally, simulation results showed …