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Uniform Strategy for Decontamination of Stored Food


The goal of the Phase II project is to design, fabricate, and test a pilot scale system capable of single-pass, high-throughput, and uniform decontamination of grain naturally-contaminated with insects, fungus, bacteria, and aflatoxin. The pilot study will demonstrate that controlled, uniform decontamination of foodstuffs (i.e., corn) with ozone can be achieved in a cost effective manner through the integration of a unique ozone generation technology with a continuous treatment grain auger and conveyance system while simultaneously focusing on personnel safety, economic feasibility, and commercial viability. This new, economically viable approach will fill the gaps that are currently evolving from the decline of treatment alternatives. It will meet the challenges that currently inhibit the utilization of safer decontaminating agents in food processing and storage facilities.<P>

The specific objectives during this Phase II project are: <OL> <LI> Design and fabricate an electrochemical ozone generation system capable of producing enough ozone to facilitate effective treatment of target contaminants within the functional system. <LI> Define the requirements for scale-up, design, and fabrication of the pilot treatment system. <LI> Evaluate and integrate all components of the pilot system into a single, functional unit of operation. <LI> Determine if the ozonation treatment process results in damage to grain, and identify whether these effects influence storage parameters. <LI> Test the pilot systems capability of reducing significant levels of insects, fungus, bacteria, and aflatoxin. <LI> Quantify the installation and operational cost projections for commercial implementation at a centralized or custom treatment center for a commercial partner(s). <LI> Integrate the engineering design of an optimized treatment system accompanied by system specifications and hardware requirements provided by the commercialization partner. </ol>These project objectives shall be accomplished through a comprehensive research, testing, engineering development, and pilot system testing program covering a two-year period. The core personnel of the team carried out a highly successful Phase I study and shall continue this interaction during the Phase II project. To supplement the capabilities and pilot testing infrastructure for the project, our academic partners at Purdue Universitys Post Harvest Education and Research Center will be conducting key evaluations of the pilot process. The experience, qualifications and intent of this team is to successfully complete the work and to position this process for transition to commercial implementation.

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NON-TECHNICAL SUMMARY: The impact of acute and chronic disease via exposure to pathogens, toxins, and chemical contaminants in food, as well as financial losses incurred from such contaminants, is significant. In an effort to increase the safety of foods, many intervention strategies have been developed, though none have been successful for uniform reduction of diverse grain-derived insect, microbial and chemical contaminants. Ozone (O3) has been shown to be a safe and effective decontaminating gas in many post-harvest processing applications, and has grown in popularity due to the lack of chemical persistence, the broad susceptibility of organisms, and the ability to make the disinfectant on-demand. Despite the promising economic and decontamination capabilities of ozone as a grain decontaminant, the generation and uniform delivery of O3 gas throughout commodities remains a challenge. Further, the correct and safe delivery of ozone into and throughout a flowing commodity stream or in storage in not trivial. In Phase II of this SBIR project, Lynntechs design and engineering team, in collaboration with academic/industry experts, will design, manufacture, and test a fully-optimized, integrated continuous ozone treatment system. The anticipated key commercialization outcome will be evaluation of the process with a corporate partner at a large scale commercial grain transfer and inspection site. <P>

APPROACH: <BR> TASK 1: Design and Fabrication of the Ozone Generation and Delivery System The proprietary EC ozone delivery system used to transport the ozone to the Continuous Ozone-Grain Auger System (CO-GAS) will be assessed for material compatibility as well as efficiency. During operation an ozone monitor will be used to determine what levels of ozone are reaching the corn along with the level of ozone that is coming out of the system. Ozone destructs will be put in place on the systems ventilation sources to prevent ozone leaks. <BR> <BR> TASK 2: Design and Fabrication of the Continuous Ozone-Grain Auger System CO-GAS This task will be to develop an auger system which will allow for the corn to mix with the gaseous ozone. The system will incorporate four main sections in which the material will be transported and treated with gaseous ozone. The systems components that will be in contact with high concentrations of ozone will be fabricated of compatible material to reduce corrosion. <BR> <BR> TASK 3: Integration and Functionality Testing The system will be retrofitted with Lynntechs 5-lb ozone generator which utilizes a patented electrochemical process that yields high concentrations of ozone (app. 15 wt%). Once the components have been obtained, Lynntech will build the unit and perform a series of functional tests. Once the system is functionally sound, Lynntech will proceed with the next task to test the effectiveness of the system on meeting the objectives set forth in this proposal. During this portion of the Phase II project, safety considerations and system failure controls will be implemented into the system. <BR> <BR> TASK 4: Bacteriological and Toxin Challenge Testing Tests will be conducted with clinically significant toxins and vegetative bacteria that have been prevalent or pose a potential threat in stored food commodities. Corn naturally contaminated with aflatoxin B1 will be obtained and utilized for the detoxification experiments. Clean yellow field corn will be used for the bacterial experiments as seeded carriers and a background load. The microorganisms that will be tested are Bacillus subtilis var. niger spores, antibiotic-resistant Escherichia coli, and antibiotic-resistant Salmonella choleraesius. An AflaTest Series-4 Fluorometer, 110V basic equipment package will be purchased from VICAM (Watertown, MA) along with AflaTest-P columns for aflatoxin analysis. <BR> <BR> TASK 5: Insect and Fungus Challenge Testing at Purdue University Once we have conducted a successful demonstration of the CO-GAS pilot system against bacteria and aflatoxins, the system will be dismantled and transported to Purdue University Post-Harvest Education & Research Center (PHERC) in West Lafayette, IN. There the pilot system will be recontructed and performance tested. Purdue will test a matrix conditions composed of exposure times and ozone concentrations on insect mortality and on populations of surface fungi. <BR> <BR> TASK 6: Economic and Commercial Viability Assessment will conclude the project, accompanied by any third party commercial evaluation of the process.

<P>PROGRESS: 2007/09 TO 2008/08<BR>
OUTPUTS: Information obtained during the course of Phase II studies has been disseminated to USDA through a year one report completed at the midpoint of Phase II studies and will also be disseminated through a final report submitted at the end of project in year 2. Additionally, our results, research progress, and year 1 conclusions have been discussed with our subcontractors at Purdue University. Limited discussions have occurred with our commercial partners at O3Co. During year 1 research we have confirmed the necessity of key reaction conditions that are necessary to achieve reduction in mycotoxin to acceptable levels. The parameters to achieve these results will be shared as necessary with our collaborators and commercial contacts during year 2 of research and commercial opportunities that follow. <BR> <BR> IMPACT: 2007/09 TO 2008/08<BR>
During Year 1 of Phase II research Lynntech has developed, fabricated and begun preliminary testing of a pilot plant-scale uniform grain processing system that is capable of eliminating all three major categories of naturally-occurring contaminants in stored commodities: INSECTS, MICROBES (bacteria and fungi), and TOXINS (mycotoxins, residual pesticides, intentional contamination). This system is based on the highly potent antimicrobial properties of ozone gas and the ability of ozone to react with mycotoxins producing a less harmful end-product. Through Phase I studies and year 1 of Phase II research we have established the parameters for successful elimination of these harmful naturally-occurring contaminants in stored grain. To this end, a pilot-scale treatment system has been fabricated and preliminary testing was started at the end of year 1. <BR> <BR> This research will continue in year 2 culminating with delivery of the system to our subcontractors at Purdue University for independent verification of the quality and capabilities of the system. A key impact of this research is to ensure that the technical and commercial objectives can he achieved while maintaining high safety standards for the equipment, treated product, and associated personnel. The economic feasibility and impact of the system must also be assessed through testing in year 2. Ultimately, this product could lead to a safer food supply for livestock while positively economically impacting the grain producer and simultaneously eliminating a waste product that would need to be disposed.

McKenzie, K. Scott
Lynntech, Inc
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