New Technologies Play Center Stage
With inspection reform in mind, industry reviews new technologies to improve meat safety-including steam pasteurization
by Bryan Salvage and Ken Krizner
Technological innovation by the private sector is an important contributor to an overall food safety strategy.
Michael R. Taylor, USDA acting undersecretary for food safety, made this statement in April while discussing "New Technology to Improve Food Safety"-which was the first in a series of three scientific and technical conferences hosted by FSIS.
It was part of USDA's outreach activities on its inspection reform proposal, which includes a Hazard Analysis and Critical Control Point program and microbiological testing.
Those with a stake in the proposal-packers, processors, academia, suppliers, consultants and consumer group representatives-met for two days in Chicago to learn about the latest in technology designed to improve food safety.
Information presented during this conference was compiled into a report and submitted as a comment on the proposal.
Twenty presentations focusing on research and new technologies were given by suppliers and members of academia.
The presentations focused on a range of technologies including steam pasteurization; rapid sanitation control using adenosine triphosphate; computer methods for building, maintaining and running a HACCP system; electron pasteurization of meat and poultry products; ozone air treatment of meat; the use of chlorine dioxide in chill water treatments; spray washing vs. hand trimming; needle-type micro-biosensors for rapid in-situ assessment of food safety; and intense pulsed light multi-hurdle pathogen reduction.
"Our goal is to reflect the perspectives of all stakeholders in [food safety], and to gain information on ways [FSIS] might further improve its role in stimulating technological innovation directed at improved food safety," Taylor says.
Steam pasteurization
Steam pasteurization of meat and poultry carcasses was of great interest to many attendees. Heralded by its developers as "a major breakthrough in the reduction of E. coli 0157:H7 in beef, pork and poultry," this technology is being patented by Cargill Inc. and Frigoscandia.
"We're utilizing proven technology that Frigoscandia and Cargill have in place today," points out Jerry Leising, vice president of Cargill's meat sector and R&D director. "The process is quite simple. It involves three steps: de-watering, steam pasteurization of the carcass surface and rapid chilling."
R. Craig Wilson, special projects director for Bellevue, Wash.-based Frigoscandia, believes steam pasteurization could do for beef, pork and poultry products what pasteurization did for milk. This "antimicrobial kill step" could replace antimicrobial rinses, which are included in USDA's proposed inspection reform plan.
Wilson, who heads up this project for his company, has a personal interest in this new process. His son is friends with several children who became ill after eating undercooked hamburger meat at Jack in the Box fast-food restaurants in the Seattle area in 1993. This E. coli 0157:H7 outbreak, which resulted in four deaths, is why Wilson wanted to head this special project.
After one year of research, Cargill and Frigoscandia went to USDA in February with the facts on steam pasteurization. Written approval came on April 1. The next step toward commercialization is testing the process in an Excel meat packing plant, which is currently underway. Frigoscandia expects to have the process on the commercial market within a year.
Behind the process
The patent-pending process and equipment were successfully tested at Kansas State University, and the process has received preliminary approval by USDA for final evaluation and testing. Tests of a prototype unit at Kansas State, which were run on more than 6,000 plates, reveals the process consistently reduced pathogenic bacteria-including E. coli 0157:H7, salmonella, Listeria and Camplyobacter-by 99.9 percent.
This process meets or exceeds recognized heat lethality data, and the equipment is designed to meet USDA specifications. Carcass color remains unaffected, and no chemicals are used.
"One of the keys to success is the control of the total process," Leising points out. "We're employing proven Frigoscandia process control systems that are already on most cooking and freezing equipment today."
The process is carried out in a completely enclosed, three-chamber cabinet, and is based entirely on time and temperature. During the de-watering process, filtered air is utilized at high volume to remove any heavy surface water that might be on the carcass surface to ensure and enhance heat transfer at the surface. This cycle takes from nine to 15 seconds to complete.
"We have the option to apply an antimicrobial spray either before or after the process," Leising stresses. "At the surface of the carcass [during steam pasteurization], we're getting a temperature of 206 degrees F or 207 degrees F, and we're exposing the surface for 10 to 15 seconds."
During the final step, chilled water [33 degrees F] is applied on the surface for 10 seconds immediately after steam pasteurization, which chills the surface temperature to 36 degrees F.
An antimicrobial rinse can be applied during this step.
Leising said the advantages of the steam pasteurization process include:
-- The ability to use high temperatures at the carcass surface enhances pathogen reduction.
-- A critical control point that reduces microbial risk.
-- The blanket effect of steam pressurization results in uniform bacterial reduction over the complete carcass.
-- This steam system requires less energy than a hot water system.
"We have estimated that we will use about 3 gallons of water a minute to make steam vs. heating anywhere from 120 gallons to 250 gallons of water to 190 degrees F in a hot water system," Leising says. "We believe this system is non-additive and environmentally friendly."
There are other advantages to steam pasteurization. Wilson says acids make for a difficult, corrosive working environment and don't provide the level of kill necessary for a slaughter line.
"Plants using the acids are taking them out because they are tough on employees," he points out.
-- The process control system's computer can identify each carcass as it enters the chamber; air and carcass temperatures can be noted; pasteurization time is automatically controlled; pasteurization temperature at the surface will be recorded; the chill water temperature can be controlled and recorded; and the carcass surface temperature (during the chilling step) can be controlled and recorded.
The last requirement is to keep the process and equipment commercially viable for the entire industry, Leising says.
The first steam pasteurization production system, which can be installed after existing carcass wash systems, is under construction. It will be installed and ready for final approval in August.
Wilson won't say how much Frigoscandia is spending on steam pasteurization, but calls it a "huge monetary commitment."
It is also not known how much this process will cost commercially, but he maintains that part of the commitment is to make it viable "from the smallest processor up to IBP."
Dave Schafer, a Kansas State meat scientist who was involved in testing the steam pasteurization process, told the Wichita (Kan.) Eagle that the pasteurization unit would occupy about 50 feet of space on the production line and could handle 700 or more sides of beef an hour.
The future
FSIS Associate Administrator Thomas Billy tells Meat Marketing & Technology that the conference established a framework where people of diverse interests regarding improving meat and poultry product safety could come together and explore encouraging and developing new technology that will accomplish improved safety.
"Several people came up to me during the conference to suggest continuing this dialogue and exchange of information, and we're certainly open to that idea," Billy says.