Source: ORBITAL TECHNOLOGIES CORPORATION submitted to NRP
NON-THERMAL SANITATION BY ATMOSPHERIC PRESSURE PLASMA (SAPP)
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
Reporting Frequency
Annual
Accession No.
0221739
Grant No.
2010-33610-20889
Cumulative Award Amt.
(N/A)
Proposal No.
2010-00514
Multistate No.
(N/A)
Project Start Date
Jun 15, 2010
Project End Date
Feb 14, 2011
Grant Year
2010
Program Code
[8.5]- Food Science & Nutrition
Recipient Organization
ORBITAL TECHNOLOGIES CORPORATION
1212 FOURIER DRIVE
MADISON,WI 53717
Performing Department
(N/A)
Non Technical Summary
The Center for Disease Control (CDC) estimates that foodborne diseases cause 76 million illnesses and 5,000 deaths in the United States each year. Among outbreaks for which the cause was determined, bacterial pathogens caused the largest percentage of outbreaks (55%) and the largest percentage of cases (55%). Currently treatment of produce is done with chlorinated water to reduce populations of pathogenic and other microorganisms on fresh produce, but it cannot eliminate them. Irradiation of certain fresh fruits and vegetables is also an option, though one many consumers are not willing to accept. It is also difficult to transition into a hand-held, commercial restaurant device. A better method for sanitation in commercial food preparation is therefore needed to improve food safety for the general public. This proposed Sanitation by Atmospheric Pressure Plasma (SAPP) technology utilizes non-thermal, atmospheric pressure (AP) plasma, which is a high-energy electrical discharge occurred at ambient temperature and pressure. Non-thermal AP plasma has recently attracted much attention as an effective disinfection and decontamination technology, due to the high removal efficiency, energy yields, and low cost. Plasma processes are well known to be highly effective in promoting oxidation, enhancing molecular dissociation, producing highly reactive species, and generating other types of high energies to enhance chemical reactions. The special properties of non-thermal plasmas, especially those produced at ambient pressure without the need for vacuum, provide a great way to generate extremely reactive species and initiate a variety of chemical reactions at ambient temperature and pressure. The proposed SAPP technology supports sanitation of food preparation surfaces and equipment, food storage containers, and surface sanitation of fresh fruit and vegetables. It would provide a scalable solution for both processing and commercial use, which is a sizeable target market. This technology is efficient in terms of mass, power, volume, waste generated, and resource (e.g., water) use. In addition to a wide range of surface sanitation uses, components of this technology may be multipurpose. For example, the specially designed power supply could be used for high voltage pulsed electric field (PEF) food treatment, an emerging non-thermal technology that can sterilize packaged homogenous liquid foods, providing a tool for both surface sanitation, and packaged food sterilization. This technology may also have applications in air and water purification.
Animal Health Component
100%
Research Effort Categories
Basic
(N/A)
Applied
100%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
71250102020100%
Goals / Objectives
The objective is to develop a non-thermal technology based on atmospheric-pressure cold plasma to sanitize foods, food packaging materials, and other hardware and working surfaces that may be encountered during food processing.
Project Methods
Atmospheric-pressure plasma is well known to be highly effective in promoting oxidation, enhancing molecular dissociation, and producing free radicals and other types of high energies. It has recently attracted much attention in food industry due to its potential of being a non-thermal and highly effective sanitation method. This proposed non-thermal plasma sanitation technology supports sanitation of food preparation surfaces and equipment, food storage containers, and surface sanitation of fresh fruit and vegetables. It is efficient in terms of mass, power, volume, waste, and resource use. The specially designed power supply could also be used for high voltage pulsed electric field (PEF) food treatment, an emerging non-thermal technology that can sterilize packaged homogenous liquid foods, providing a tool for both surface sanitation, and packaged food sterilization. During this Phase I effort, a non-thermal plasma prototype will be designed, built, and optimized. Its sanitizing performance will be evaluated on tomato, lettuce, polypropylene, and Teflon substrates, all of which will be inoculated with E. coli O157:H7.

Progress 06/15/10 to 02/14/11

Outputs
OUTPUTS: Interim report delivered to USDA in October 2010. Final report delivered to USDA in May 2011. PARTICIPANTS: Dr. Yonghui Ma - Principal Investigator; Barry Arneson - Electrical Engineer; Adam Marten - Mechanical Engineer; Dr. Amy Wong - Subcontractor - University of Wisconsin Food Research Institure TARGET AUDIENCES: The target audience is anyone who wants to reduce microbial contamination of food. PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
The Sanitation by Atmospheric Pressure Plasma (SAPP) technology developed in this SBIR utilizes non-thermal, atmospheric pressure (AP) plasma, which is high-energy electrical discharge at ambient temperature and pressure. During this Phase I project, efforts were concentrated on the scientific, technical, and commercial merit and feasibility of using non-thermal plasma for sanitation of food stuffs and food-preparation-related tools and facilities. Two different types of SAPP prototype reactors were built to evaluate certain design factors before a final SAPP design was reached that used dielectric barrier discharges (DBD) to create a plasma jet. Several iterations of this DBD plasma jet reactor were designed, built, and tested. Its efficacy in killing microorganisms was evaluated by treating Teflon coupons inoculated with Salmonella strains. Some of the process parameters were optimized to achieve the maximum kill rate. A custom-made power supply was also built to drive the prototype SAPP reactors, which may also be used in the future for high-voltage pulsed electric field treatment. Through the microbial tests, it was found that, among the several different processing gases/gas mixtures, argon with the addition of a small percentage of oxygen (2.5-5.0% by volume) has been the most effective in most cases. Additional tests were conducted to determine the effective killing zone and to maximize the distance between the substrate surface and the orifice of the plasma jet. It was found that, with an appropriately designed reactor setup, the after-glow zone of the plasma jet can be even more effective than a direct contact treatment, killing as much as 99.96% of inoculated Salmonella.

Publications

  • No publications reported this period