Brief Summary of Minutes of Annual Meeting

Summary of Accomplishments of NC-2013 Participation Stations California • Utilize innovative methods to characterize food materials. Magnetic resonance imaging was used to characterize and optimize mixing systems for food and consumer products as well as food systems that are designed for better delivery of bioactive compounds. Positron emission particle tracking was utilized to monitor mixing in model food systems during simulated gastric digestion. • Develop new and improved processing technologies. The influence of thermal and high pressure processing on nutrient stability and bioaccessibility of fruit and vegetable juices is under investigation. This ongoing study will allow for optimization of juice processing to provide greater health benefits from juice. • Develop mathematical models to enhance understanding of, and optimize food processes. In a collaboration with MI station (MSU, Brad Marks), a study was completed to understand the inactivation of Salmonella in almond meal during simulated gastric digestion. Inactivation modeling is ongoing. Diffusion processes during food digestion have been investigated to optimize food processing as it relates to food breakdown. • Develop pedagogical methodologies for improved learning of food engineering principles. A food processing laboratory course was developed and offered to undergraduate food science majors. Addition of modules developed by NY station are planned for 2015. Georgia • Dielectric properties measurement: Dielectric properties of broccoli powder at different moisture contents were determined over a temperature range of 20-80°C, and frequency of 1 to 30 MHz. • Human digestion system: Develop novel artificial stomach and intestinal models to study food digestion kinetics as affected by food matrix. Three innovative gastro-intestinal models were developed including a Dynamic Gastric Simulation Model (DGSM), an Advanced Stomach Model (ASM), and a Dynamic Duodenum Model (DDM). • Radiofrequency heating: Thermal inactivation of STEC and nonpathogenic E. coli in packaged non-intact steaks heated up to 60°C or 65°C was carried out. • Radiant wall (Infrared) heating: Instrumental and sensory quality of potato strips baked in a Radiant Wall Oven (RWO) was evaluated and compared to deep-fat fried and conventional oven (CO) baked samples. • Drying: Drying techniques have been developed to process underutilized agricultural materials, while maintaining good sensory and nutritional quality. These include bagasse and similar materials left from juice processing, including apple and tomato. • Microencapsulation: Develop methods to microencapsulate blueberry anthocyanins, ?-carotene and tannic acids. Ionic gelation and spray drying were studied as the two different microencapsulation methods. The release kinetics of bioactives in simulated GI conditions was studied as affected by different wall materials. • Food Engineering Fundamentals is a required course for food science students. Students’ feedback reflected a preference for more practice in problem solving. Since 2013, “Flipped Classroom” technique was used in the course, where students watched videos outside the class to learn basic principles, and in the class practiced problem solving through group discussion and active interaction with the instructor. Student evaluations indicated their preference for this new teaching style. An improved performance of students on their homework and tests was observed. • Validating Food Safety in Meat Processing workshop (September 22-23, 2015): This workshop was co-sponsored by the Southeastern Meat Association and The University of Georgia Food Science Extension. It covered a broad range of topics from food safety and quality control, sanitation programs, storage, system validation, microbial intervention, and regulatory programs. Hawaii • A combination of pulsed electric field (PEF) and oscillating magnetic field (OMF) was used to achieve an extension of the supercooled state in beef steak with an internal temperature of -4.5 °C for up to two weeks. The combined use of PEF and OMF maintains the vibrational motion of water molecules thus affectively inhibiting sudden ice nucleation. Shock-induced freezing will occur in materials while in the supercooled state however, shock-induced freezing was not observed after the intentional administration of external physical stress to the treated samples. This was confirmed by microstructure images of the treated samples obtained using an inverted contrasting microscope. Micrographs of the treated samples returned to room temperature for up to 30 minutes showed no ice crystallization suggesting a magnetic “memory” effect from the applied OMF. Drip loss, texture analysis, pH and lipid oxidation (TBARS) for supercooled beef steak samples were evaluated after 1, 3, 7, 10 and 14 days as compared to control samples. The PEF and OMF supercooling was found to maintain fresh beef steak qualities for up to two weeks, thus suggesting this novel preservation technique may be utilized to preserve the organoleptic qualities found in fresh meats. Idaho • Utilize innovative methods to characterize food materials. Current projects focus on fundamental rheological properties of foods, and how those properties connect to structure and texture. Projects include UHT milk friction, yogurt flow and friction, cottage cheese dressing rheological behavior, mechanical behavior of reduced fat cheese, fundamental properties of polysaccharide derived from camelina seed, and fracture behavior of solid baby foods. • Develop pedagogical methodologies for improved learning of food engineering principles. The Food Engineering class was converted to flipped format. Students reviewed material before class and worked on application problems in class. Responses to this flip were positive, although students requested more problem-solving guidance. Problem-solving modules explaining the problem-solving process step-by-step were developed for each topic taught; completion of these modules will be required in future courses. Illinois • Ultrasonication in combination with low hydrostatic pressure and mild heat, manothermosonication, was used to modify functional and emulsifying properties of soy protein isolate. In another method, ultrasonication is combined with a pH shifting process to modify soy and pea protein isolates. The nano-protein aggregates showed good protection of vitamin D3 against UV light exposure. In another test, an ultrasound fresh produce washer was developed. Ultrasound enhanced the efficacy of a traditional wash with chlorine. • Hybrid Mixture Theory based unsaturated fluid transport equations were coupled with poroviscoelasticity and multiscale heat transfer equations and solved for frying of foods and expansion of starch during extrusion. Models were validated by making comparisons with experimental data. • Collaborations: 1. Illinois (H. Feng)-USDA-ARS (S. Luo). 2. Illinois (P. Takhar)-Nebraska. 3. Illinois (Y. Lee)-California (G. Bornhorst). Iowa • Sensory evaluation by a trained panel of model high-protein nutrition bars formulated at 30 % protein with extrusion-processed milk protein concentrate (80%, MPC80) was carried out during accelerated storage at three temperatures. Effect of MPC80 particle size reduction via jet-milling on instrumental and sensory texture of 30% protein nutrition bar being carried out currently. The goal of the Aronia Jam and Jelly study is to have the Food and Drug Administration (FDA) include Aronia berries in the list of approved fruit for jams and jellies in Title 21. The Jam and Jellies project involves donors sending samples of their berries, recipe, and their jam or jelly for testing. The jams and jellies received are tested for water activity, degrees brix and pH, in order to make sure that they comply the FDA standards. To date, 37 jams/jellies have been received and tested. Overall, 14 jams/jellies have met all 3 criteria. • Invasive Species Project: The Spotted Wing Drosophila is an invasive species that is affecting berries grapes and other fruits. The goal of this project is to develop recipes that can be used with the damaged berries. Berries that are being tested are blackberries, raspberries, Aronia berries and strawberries. The project is across multiple states and involves recipes for farmer’s markets, restaurants and grocery stores. Recipes that are made are then tested for quality, shelf life and microbial factors. A recipe book is going to be developed and published at the end of the project so farmers can use their infested berries and not take a huge loss on their crop. • The Influence of Radiation on the Quality of Milk and Rennet Enzymes used in Cheese Making during Long Term Space Mission: This project is the final year of a five year study tracking the effects of irradiation and stored milk powders and rennet enzyme used for making cheese. Rennet and low heat treated dried milk were gamma irradiated at different levels and then used to make the curds for cheese manufacture. Zero gray, one gray, three gray and five gray levels of irradiation were tested for both the rennet enzyme and powdered milk. The time in seconds to reach a viscosity of 100,000 centipoise was determined for each milk and enzyme combination tested. Other factors such the effects of quantity of enzyme and the effects of sealing enzyme containers were also investigated • Collaborations: University of Minnesota Dairy Science faculty, and South Dakota State Univ Dairy Science faculty collaborated in this project. Extrusion of milk protein concentrate in a food grade facility at UMN was done. Enzyme cross-linked MPC80 were obtained from SDSU. Exchange of ideas regarding using milk protein concentrates in food applications discussed. University of Illinois, University of Kentucky, NASA contributed to the radiation study. Analysis berry samples and jams/jellies received from Nebraska, Illinois, Minnesota, California, and other states. Kentucky • As a newly appointed faculty member at the University of Kentucky Department of Biosystems and Agricultural Engineering, I spent the last year developing my teaching portfolio, building my lab, writing proposals and recruiting students and technical staff to support my programs. I have since purchased two state-of-the-art instruments for thermal and rheological properties of food testing, DSC and Rheometer (TA Instruments, USA). I have so far trained one undergraduate and visiting PhD students, admitted 3 graduate students (1 MSc and 2 PhD), and I am mentoring one post-doc. I am also building research programs that will support the agricultural production and the food processing sector in the commonwealth of Kentucky and nationally. • During this period I wrote nine proposals to source funding for different programs (teaching, training, equipment and research), that form the core of my mandate, from various agencies namely University of Kentucky Food Connection, Kentucky Science and Engineering Foundation Fund, Burroughs Wellcome Fund, University of Kentucky e-Learning Program, USDA-NIFA Foundational Program (FASE Equipment, Borlaug Fellow Program and exploratory research grants), Kentucky Small Grain Growers Association and the Bill and Melinda Gate Foundation. So far I have been successful in 4, and am awaiting the outcome of one. • Collaborations: With several of colleagues in some of the funding applications mentioned above namely Drs. Adedokun and Xiong of Animal and Food Science, Drs. McNeill and Mike Montross of department of Biosystems and Agricultural engineering, all of University of Kentucky. Also collaborated with Dr. Subbiah of University of Nebraska. Some of these colleagues are members of NC1023, while some belong to other USDA multistate groups. Michigan • Advancing fundamental science and application: Patent submission for new instrument to dynamically measure thermal conductivity of conduction-heated foods (collaboration with Jeyam Subbiah at UNL); • Developing and testing improved methods for validating and adopting low-moisture food pasteurization technologies, in collaboration with Juming Tang and Meijun Zhu (Wash), Jeyam Subbiah (Nebraska), Elizabeth Grasso (Illinois Institute of Tech), Harshavardhan Thippareddi (GA), Denis Gray (NC) Nathan Anderson (FDA) • Develop outreach programs: 1) NFSI grant “An Integrated Approach to Enhance the Microbial Safety of Fresh-Cut Fruit and Vegetable Products during Processing, Packaging, and Retail Distribution.”; 2) Cal Poly, Rutgers, The Ohio State University, International Food Protection Institute, the Institute of Food Safety and Health (IFSH) – Illinois Institute of Technology and FDA. Maine • Quality attributes such as color, texture and pH of oysters at various times and temperatures combination was investigated and compared with commercially available oyster products. A detailed discussion with Dr. Tom Yang, Senior Food Technologist, Combat Feeding Directorate, United States Army Natick Soldier RD&E Center, Natick, MA on providing facility for oyster processing using high-pressure unit at Natick, MA for performing analysis was chalked out. • Green technologies were used to extract bioactive compounds from plant materials. Microwave and ultrasound assisted extraction were used for the extraction of phenolic bioactives from food as well as medicinal plants. • Plant and animal-based allergenic proteins were processed using various nonthermal and thermal technologies and analyzed for their potential reduction in allergens. Minnesota • Conduct research on analytical tools for non-destructive and non-invasive evaluation of food materials and products. Nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) were the focus of our research efforts. These non-destructive and non-invasive techniques are suitable for the study of state of water and biopolymers, structure, distribution of water, fat, and temperature in foods, and heat and mass transfer in foods. During this reporting period, we further improved fast imaging techniques for small MRI instruments for low moisture foods and biological materials. We are expanding our research to analysis of microbial activity as a tool for food safety control. This effort is important to facilitating industrial use of low cost NMR and MRI instruments for monitoring food processes, materials, and products. Major obstacles to be overcome include low signal to noise ratio of the low field system, low gradient response time, and other hardware issues, and the new software development for the low field system. Specific accomplishments include: 1) NMR and MRI techniques were improved for study of low moisture content foods; 2) Use the NMR/MRI techniques to study physiochemical properties and shelf life stability of food products; and 3) Expansion to microbiological analysis. This research is in collaboration with Harry Xie of Bruker Optics and researchers in Nanchang University, China. • Minimal processes that preserve and improve the nutritional values, health benefits, and safety of food products. During this reporting period, we focused on 1) Applied our non-thermal processing platform (NTP) to improve the bioavailability of sulforaphane from broccolis seeds, phenolics from potato peel, and ginsenosides from ginseng root. 2) Tested the non-thermal pasteurization effect of high pressure homogenization. A non-pathogenic E. coli strain was used as marker. After one pass through the high pressure homogenizer, more than one log of reduction was observed. Multiple passes were tested; however, the residual solution from previous pass created a problem for accounting for the effect of number of passes. This problem is being addressed. 3) Conducted preliminary study on non-thermal plasma pasteurization of milk powders. New Jersey • Process non-uniformity during high hydrostatic pressure processing of heterogeneous foods. Accomplishments included 1) In a model systems consisting of 2% glass wool in gel showed 1 log cfu/g less inactivation of Listeria innocua compared to pure gel. No differences were found in the inactivation of bacteria at different positions in the model system consisting of gel with wood inclusion. The inactivation of yeast was 1 log cfu/g less in gel containing 2% POP particles compared to pure gel. It was determined that von Mises stress and pressure gradients formed very close to the inclusions. 2) During real-time inactivation measurements due to HPP, cell membrane damage was detected using propidium iodide during pressurization and holding time, but not during depressurization. • Effect of Surface Roughness in Model and Fresh Fruit Systems on Microbial Inactivation Efficacy of Cold Atmospheric Pressure Plasma. Accomplishments: 1) Model system (closed coat sandpapers with roughness- 6 µm to 16 µm) showed a 0.52 log higher inactivation of E. aerogenes on the smoothest sandpaper (2.08 log inactivation) and the difference was statistically significant from the roughest sandpaper. Fruit surfaces results showed 1.25 log higher inactivation on apples (1.86 log inactivation) which were the smoothest and the difference was statistically significant from the roughest fruit which were cantaloupes. 2) Emission spectrum from OES indicated the presence of reactive oxygen and nitrogen species with potential to cause microbial inactivation. • High pressure assisted infusion of calcium in PME pre-treated baby carrots. Accomplishments: 1) The amount of calcium infused with HPP was significantly higher than that infused by vacuum infusion and osmotic infusion. 2) We were able to achieve infusion of calcium up to 150 mg/serving of carrots (equivalent to 15 % RDI) without significantly affecting their texture and color. New York • Structural changes of Milk Protein Concentrates induced by High Pressure Processing (HPP) were studied. The project used the combined expertise in milk proteins / protein structures of Dr. Moraru’s group at Cornell University with the HPP expertise of Dr. Karwe’s group at Rutgers University. This research illustrates how HPP which may enable new applications for milk proteins in a variety of new dairy-based and protein-fortified foods with unique structure and texture. Additionally, these results present some evidence for substructure in the casein micelle. • Understanding the mechanism of attachment and internalization could lead to the prevention of future outbreaks on fresh fruits and vegetables. The goal of this model was to use a Lagrangian particle tracking simulation of a spherocylinder shaped bacteria, Escherichia coli, to determine the dominant forces and the effect plant surface structures have on attachment. Simulation results are being validated against literature experimental data on attachment to microfabricated plant structures: stoma, trichomes and grooves. • We are currently working with faculty members from ~10 universities (includes Cornell Food Science) in developing and implementing the learning modules. We have now implemented the latest module in Univ. of IL Food Science class. The results are coming in as we write this document. Same implementation is currently underway in Rutgers Univ. Ohio • Inactivation of Escherichia coli O157:H7 as affected by a combination of gaseous ozone and vacuum cooling, type of fresh produce, and the efficacy of a pre-washing step, integrated into the gaseous ozone treatment was comprehensively investigated and optimal conditions identified. • Enzyme activities in tomato homogenate as well as on cellulose were significantly influenced by electric field frequency and field strength. • A study on pressure crystallization effects of binary fat blend indicate that pressure treatment significantly modified nanostructure, microstructure and polymorphic properties of the fat blends. • High pressure homogenization treatment efficacy of beverages was evaluated in terms of particle size distribution, microstructure, viscosity, and macro-rheology. Furan formation was accelerated by heat treatment and inhibited by high pressures. • A model has been developed for prediction of specific heat capacities of lipid foods based on carbon number and level of unsaturation. • Frozen food shelf-life can be maintained at temperatures above the current industry standard. • Alkaline cleaning solutions may be re-used or re-claimed to improve the efficiency of food plant cleaning operations. Oregon • Food materials (berry fruit, surimi, and milk) and food processing byproducts (fish bones, squid pens, fruit and wine grape pomace) were characterized in respect to their chemical compositions, bioactive compounds and functional properties. • Impact of milk hauling on raw milk quality were investigated. The effect of lyophilized salmon blood plasma (SPP) on the gelation of Pacific whiting surimi under different ohmic heating conditions were studied. • Value-added products, including surimi from fish proteins, fruit pomace fortified food product and biodegradable packaging containers from fruit pomace were developed and characterized. • Nano-scale fish bone was used as an ingredient to increase the bioavailable dietary calcium of seafood products, such as halibut steaks, tuna steaks, salmon steaks or burgers, fish sticks, or other products where ingredients are mixed and formed into shapes for consumption. • Nanocellulose based coating and encapsulation technologies were developed to retaining anothcyanin pigments and stability in canned and high hydrostatic pressure (HHP) processed blueberries and cherries in light syrup. Nanocellulose fibril and crystal based coatings were also developed to prevent cherry rain cracking and postharvest quality loss of fresh fruits. • HHP (200 or 250 MPa for 5 min) at low temperatures (15, 5 and 1.5 °C) was investigated for inactivating Vibrio parahaemolyticus in oyster homogenates. Inactivation of V. parahaemolyticus cells in oyster homogenates was greatly enhanced by lowering the processing temperature from 15 to 5 or 1.5 °C. • Outreach programs were implemented to disseminate the research findings and help the stakeholders for ensuring their product safety and quality. This includes HACCP workshop, surimi school, better food processing control school, food quality analysis short course, etc. In additional, websites were provided for delivering the latest information to the stakeholders. Pennsylvania • Cocoa products are a rich source of dietary polyphenols. The objectives of this study were to: (1) develop a new method for quantification of PaCs using high performance liquid chromatography coupled with electrochemical detection (HPLC-ECD), (2) investigate the effects of alkalization of cocoa powder on color, TP, and PaC composition, and (3) investigate the effects of whole bean cocoa roasting on color, TP, PaC composition, and aroma. • All alkalization treatments caused a significant change in color (p < 0.0001). PaC loss was modeled using a two-phase exponential decay model. Roasting treatments reduced TP up to 40%. All treatments at 190?C, 170?C, and 150?C except 10 min, significantly decreased EC content and significantly increased catechin content as compared to unroasted beans (p < 0.05). For all PaCs DP 2-5, a decreasing trend in PaC content was observed with increasing time and temperature of roasting. • Alkalization of cocoa powders does not reduce these compounds to the extent previously believed. Roasting cocoa beans at 170?C or above results in the highest production of DP 6 and 7 PaCs. In addition to meeting the sensory quality based on consumer needs, processing conditions used to produce cocoa products should confer greater health benefits to consumers. • Collaborations: Dr. J. Lambert (Penn State) South Dakota • Develop new and improved processing technologies (HPP and Ultrasound): Endospores of Bacillus licheniformis (ATCC® 6634), Bacillus coagulans (ATCC® 12245), and Geobacillus stearothermophilus (ATCC® 15952) were spiked in sterile nonfat milk, and subjected to high intensity batch ultrasonication treatment at different amplitudes (80 and/ or 100%) and durations (1 to 10 min). Increasing the amplitude from 80 to 100 % did not result in enhanced inactivation of G. stearothermophilus endospores. However, an increase in the duration of ultrasonication from 1 to 10 min significantly increased the inactivation of endospores of all three species. About 48.96 % of the G. stearothermophilus endospores were inactivated by ultrasonication alone; whereas, ultrasonication and pasteurization combined increased the inactivation to 65.74%. Inactivation of endospores could be further enhanced to 75.32% by ultrasonication and higher heat (80?C/1 min) combination. Endospores of B. licheniformis and B. coagulans were inactivated to a lesser extent compared to G. stearothermophilus spores. Ultrasonicated B. licheniformis endospores germinated in higher numbers when compared to untreated endospores resulting in their greater inactivation during the combined treatment. As the structures of ultrasonicated spores were apparently unaffected, the decrease in thermal resistance after ultrasonication might have been due to spore germination rather than mechanical damage to the spore. Tennessee • We continued to study novel emulsions, microemulsions, nanoemulsions, and biopolymer nanoparticles as delivery systems of antimicrobials, nutraceuticals, probiotics, and pigments and characterized physical, chemical, biological, and microbiological properties of these systems. We also studied technologies improving physical properties of food biopolymers. Collaborations with Dr. MaryAnne Drake and several others at North Carolina State University are collaborators in a USDA Organic Research and Extension Initiative (OREI) project. • We continued the OREI project with research and extension objectives to formulate novel wash solutions to enhance the microbiological safety of organic fresh produce. We completed the Center for Produce Safety project to study essential oil coatings to improve microbiological safety and quality of cantaloupes during shelf-life storage. We continued to study delivery systems of antimicrobials, pigments, nutraceuticals, and probiotic bacteria to improve their stability and bioactivity. We used various techniques to characterize physical properties of food biopolymers and develop technologies to improve these properties, including dispersion stability, turbidity, and turbidity, and rheology. Texas (Texas AgriLife Research) • Characterization of biopolymers for use as matrices for encapsulation of hydrophobic compounds. Work is still in progress. Looking forward to collaboration with Oregon and other stations. • Intervention steps to reduce the risk of Listeria contamination of fresh produce (Rosana Moreira, Elena Castell-Perez). Accomplishments: 1) Assessed the effectiveness of washing treatments as a postharvest practice to minimize the growth of Listeria and L. innocua on fresh-cut cantaloupe and romaine lettuce leaves under different storage temperatures. 2) Dynamic models can be useful for manufacturers to evaluate the impact of handling practices (storage temperature and washing treatments) on the growth of Listeria in the selected fresh produce. 3) Growth models were used to develop quantitative risk assessment models. Collaborations: We are currently exploring potential collaborations with other stations interested in predictive microbiology to develop good handling practices of fresh produce. Example: Michigan station. • Nanotechnology approaches for design of antimicrobial delivery systems and biosensor for food safety applications (Carmen Gomes). Accomplishments: 1) Assessed antimicrobial, antioxidant and anti-carcinogenic activities and physico-chemical characteristics of bioactive compounds from guabiroba fruit (Campomanesia xanthocarpa O. Berg) and its nanoencapsulated extracts using PLGA as the carrier. 2) Assessed the use of stimuli-responsive polymers to enhance biosensor performance (i.e., detection limit, range, sensitivity, response time) to detect foodborne pathogens using electrochemistry approaches. 3) Assessed morphological and release profile of nanoparticles formulated with poly(DL-lactide-co-glycolide) (PLGA) and lupeol and its effect on human cells. 4) Optimize the synthesis process of thermally-responsive poly-n-isopropylacrylamide (PNIPAAM) nanoparticles for controlled release of antimicrobial hydrophobic compounds. 5) Designed a process for nanoencapsulation of essential oil (trans-cinnamaldehyde) using alginate and chitosan biopolymers. 6) Assessed the effects of nano-encapsulated natural antimicrobial application on quality of fresh-cut romaine lettuce. Chitosan-PNIPAAM encapsulated cinnamon bark extract (CBE) were compared to free CBE and control (no treatment) treatments at 3 concentrations levels once sprayed for its effects on fresh-cut romaine lettuce quality over 15 days of storage at 5oC. Washington • Developed thermal process procedures based on 915 MHZ single mode microwave assisted thermal pasteurization system (MAPS) developed at WSU for production of five chilled ready to eat meals. Validated microbial safety of the samples by a third part (Micro-Chem, Seattle), and conducted sensory tests at US Army Natick Soldier Center for storage of 9 wks at 7 and 12 C. Supported FDA filing activities conducted by Ameriqual Foods (Evansville, IN) on a pilot scale 915 MHz single-mode microwave assisted thermal sterilization (MATS) system based on patents of WSU. The filing received acceptance in March 2014. Supported five food companies exploring new food formulation and processes on WSU Pilot Scale MATS and MAPS systems. • WSU offered a one week bookcamp on microwave sterilization and pasteurization technologies, for engineers from food companies and research institutions in USA, Australia, Japan, India. 12 food companies in Evansville, IN, May 2015. • Designed and developed multilayer polymeric films for pasteurization processes. These films utilized coated PET, nylon and/or EVOH as core barrier layers. The barrier layer was protected with PP and PE layers. • Examined the influence of oxygen and water vapor barrier properties of multilayer films on the chemical changes and shelf-life of different foods. The findings will help food companies to select films for desired shelf life of selected products. • Collaborations: As part of a USDA AFRI Project (No. 2011-68003-20096 – Control of Food Borne Bacterial and Viral Pathogens using Microwave Technologies, Juming Tang PI and Shyam Sablani Co-PI) works with a team of food microbiologists and virologists led by Dr. Michael Davidson and Doris D’ Souza at the University of Tennessee in a five year (2011-2016) to study heat resistance of viruses in different food matrices. The research provide scientific data for development of microwave pasteurization processes for control of viruses in ready to eat meals. Also, Tang’s group works with Dr. Bradley Marks’ team at Michigan State University in developing thermal control of salmonella in low moisture foods. They also collaborate with Decagon Inc. in Pullman, WA, a leading manufacturer of water activity measurement devices. Wisconsin • Gunasekaran. A gold nanoparticles (AuNP)-based thermal history indicator (THI) for monitoring lowtemperature storage was formulated. Initially, the color of the THIs is slightly pink, but after a 90-day storage in the freezer, as both the size and shape of the AuNPs change, the color of the THIs turns to red. After 90 days the absorbance peaks of THIs held at room temperature are red-shifted from 538 to 572 nm and possessed larger amplitude compared to those stored in the freezer. The color change is a function of both storage time and temperature. The THIs experiencing higher temperature treatments exhibit a more intense color change which is attributed to a localized surface plasmon resonance effect. Thus, the visual color change can provide information regarding the material thermal history. • Hartel. By controlling process conditions (dasher speed) and formulation (emulsifier, fat and air content), we have shown that we can create ice creams with a wide range of partially destabilized fat, which appear as large fat globule clusters. These clusters have been shown to be one of the most important structural parameters that affect melting properties of ice cream. • We are also investigating arrested (or partial) coalescence of fat globules of different composition under controlled conditions to better understand how these clusters form during processing. We are also further evaluating the potential use of particles at the interface to induce arrested coalescence and build fat globule structures without internal crystalline fat.

See attached file for publication from each station.