Egg Industry News and Commentary

  —  Jun 16

 
Application of Radio Frequency Technology to Pasteurize Eggs

   

The Agricultural Research Service recently issued a press release on the application of radio frequency technology adapted by Dr. David Geveke to pasteurize eggs.  Dr. Geveke is a chemical engineer located at the Agriculture Research Service Food Safety and Intervention Technologies Research Unit in Wyndmoor, PA.

The latest press release is basically similar to a previous release in 2013.

EGG-CITE posted two commentaries in 2013 and 2014 which are reproduced below:-

  

 

In the intervening years since 2013, RF pasteurization technology may have been refined but the reality is that it is a solution looking for a problem.  The market for pasteurized eggs is extremely small, representing less than one percent of shell eggs consumed.  This market is satisfied by an immersion process developed by L. John Davidson in the 1990s.

After a series of bankruptcies and restructuring of the Pasteurized Egg Corporation, the successor, National Pasteurized Eggs was formed in 2011 to market the concept. In 2016 the Company, including patents and the brand were acquired by Michael Foods.

The comment in the press release that this technology could reduce “egg-borne Salmonella illness (SE) by up to 85 percent, or more than 110,000 cases a year is arrant nonsense.  There has not been a documented case of SE acquired from eggs produced by commercial flocks operating under the FDA Salmonella Prevention Rule, a State EQAP, the UEP Five-Star Safety program or their combination since the DeCosters’ Wright County, IA outbreak in 2010. This episode represented a complete aberration as evidence suggested that the DeCosters operated their farms and packing plants contrary to industry standards, resulting in guilty pleas by the Defendants.

    

USDA and Princeton Develop RF Pasteurization for Shell Eggs -- Sep 3, 2013

The Princeton Plasma Physics Laboratory and the U.S. Department of Agriculture-ARS have developed a radio frequency (RF) pasteurization process for shell eggs.  The prototype is capable of inactivating potential Salmonella infection in eggs by heating. 

  

It is claimed that the process will not affect the physical appearance or properties of the albumen.  This is a deficiency with the current batch hot water immersion pasteurization process used commercially.

While pasteurization of shell eggs is appropriate for consumers with health problems including immunosuppression, there does not appear to be a great demand for pasteurized shell eggs this is evidenced by the fact that less than 1% of all shell eggs are subjected to heat pasteurization.  This new technology, even if effective and financially feasible, will have a limited market, probably restricted to specific food service applications.  The bulk of egg liquid used in food manufacturing processes is subjected to conventional plate pasteurization in high-capacity plants.

Although the small prototype has proven effective under laboratory conditions and is the basis of a patent application, scaling up the device to commercial level will obviously be a challenge. It will take many years to bring to market, if ever. A requirement for commercialization would be that the total of both fixed and variable components of cost to process eggs should be below 10 cents per dozen and process rates of 200 cph for each installation should be attainable.

The development of in-shell pasteurization should be viewed against declining demand for this technology since the prevalence rate of SE is extremely low. It is highly likely that within 2 years SE will be eradicated from the commercial egg industry in the U.S.  It is noted that only 0.25% of flocks in the U.K yield either Salmonella Enteritidis or Salmonella Typhimurium.  The prevalence rate of SE in the U.S. is low and declining given recent figures on SE positive environmental samples obtained from farms undergoing comprehensive FDA inspections. The complementary goals of eradication in flocks and elimination of egg-borne SE in consumers is achievable given the current application of diligent biosecurity, sourcing chicks from NPIP-certified hatcheries, vaccination and maintaining a cold chain from production to point of sale.

Promoting pasteurization of shell eggs on the presumption of a high egg-borne incidence rate in U.S. consumers of product produced in accordance with the FDA Egg Safety Rule is disingenuous. To be charitable statements in support of this project reflect wishful thinking on the part of scientists developing complicated solutions to non-existent problems.

 

RF Pasteurization of Shell Eggs.

Apr 2, 2014

 

    

A release from the USDA in Agricultural Research March 2014 Edition, highlights research leading to a prototype shell-egg pasteurizer applying RF (radio frequency) heating. Studies and development were conducted at the ARS Eastern Region Research Center in Wyndmoor PA. in association with the Princeton Plasma Physics Laboratory in Plainsboro, NJ.

The announcement does not presage any breakthrough which might have any practical or economic impact on the U.S. egg-production industry given the state of development and timing of the invention. When considering the initiation of any research project, especially if it involves public funding and resources the following questions should be addressed by administrators:-

  • Is the technology needed?

Many claims relating to preventive approaches to egg-borne salmonellosis of consumers  perpetuate the blatantly overstated figure of “1 in 20,000 eggs”. This “guestimate” of prevalence was based on administration of a high-dose (108 cfu) of SE to susceptible hens under experimental conditions This assumed prevalence is totally outdated in the light of current industry management, biosecurity procedures and intensive vaccination. Effectively the problem of egg-borne SE infection from commercial flocks is negligible as evidenced by structured surveillance. (See Time to Dump the 1 in 20,000 Myth posted on EGG-CITE January 31st 2013). Currently the problem of food-borne SE is now attributed to other than table eggs from commercial flocks over 3,000 hens operated under the UEP 5-Star Prevention Program and complying with the FDA Salmonella Prevention Final Rule of 2010. It is estimated that the market for in-shell pasteurized eggs represented by some food service and consumer segments is less than 1 percent of current U.S. production requiring the output from at most approximately 2.5 million hens.

  • Is the technology practical and financially feasible?

According to the USDA release the prototype involves “positioning an egg between two electrodes that send radio waves back and forth through it while it is rotated and sprayed with cold water” This process is followed by immersion in a water bath. Considerable technical development will be required to mechanize and automate a two-phase process to achieve commercially acceptable pasteurization rates projected to be in the region of 200 cph with positive feedback control of the process.  At this time no firm estimates of either capital or operating cost for a workable model have been developed which could be used to confirm the potential for commercial application or to justify further development requiring public funding. Subjective stabs at cost suggest “twice the current commercial process in the U.S. which suggests North of 50 cents per dozen. The release appears to be intended to generate commercial interest leading to a license and royalty agreement for a private sector entity to invest in further extensive development, approval and commercialization.

  • Are alternative systems in operation?
  • The patented Davidson process is used by National Pasteurized Eggs. This is a two- stage batch immersion process which pasteurizes eggs by application of heat in warm water.
  • A similar immersion water bath system has been developed in Korea and is in operation in Asian countries   
  • A consortium of producers in the Midwest have commenced pasteurizing eggs commercially using a patented two-stage water bath and ozone process developed by the Ohio State University
  • Scientists at the Council for Scientific Research in the Republic of South Africa have developed a continuous flow microwave irradiation and infra-red heating system which can be installed in or adjacent to a plant or can be deployed as a portable unit. When the feedback control system is finalized this technology will be available worldwide for application.
  • Is proposed technology superior to existing systems? 

Since the RF pasteurization module is a prototype it is not possible to determine whether there are any advantages or problems with respect to processing efficiency or cost.  The Davidson System results in some coagulation of the albumen compared to the South African microwave unit which does not degrade the physical appearance of either the inner or outer egg white.  The thermal immersion process results in a low-level of shell cracks depending on integrity of egg shells produced by the supply flock.  It is anticipated that the RF system may also demonstrate this problem if RF heating or the secondary thermal immersion stage are at a sufficiently high temperature to damage the shell of eggs previously stored at the statutory 45F before off-line processing and pasteurization.  This is a reasonable presumption give the temperature required to destroy Salmonella which may be present in the albumen in addition to the yolk.

In reviewing the proposed RF technology the question arises as to why ARS scientists are in effect “reinventing the wheel”.  It is recognized that this project was initiated about five years ago with the current team intensifying development in 2011. It is however unjustified to expend time and money on a project if there is doubt as to ultimate commercial application and acceptability.  Did those responsible for approving the project actually review the alternatives, the potential market and develop cost projections?  It is conceded that RF technology is widely used in the food industry and in many applications it is cost effective, especially for liquids. A major manufacturer of liquid pasteurization equipment in the EU markets an RF-module to produce high-quality, extremely long shelf-life, pasteurized egg liquid which retains functional properties and was developed specifically for confectionary.

A further question is why scientists are working on a technology to pasteurize eggs in Pennsylvania when the ARS has an Egg Safety and Quality Research Unit at the Russell Research Center in Athens GA?

Perhaps the research group in Wyndmoor might be more acquainted with the realities of the egg industry and the constituency it serves if they reviewed their projects with colleagues in industry including those familiar with processing and equipment design, rather than operating in pristine isolation.  As with many USDA-ARS projects which involve the expenditure of public funds, there is insufficient rigor in justifying a program at the time of conceptual planning or in assessing the potential for commercialization. Additionally projects proceed at too slow a pace to be relevant when completed.

Contrast the support of research projects by the U.S. Poultry and Egg Association.  Applicants for funding submit brief proposals indicating purpose and methodology.  Proposals are reviewed by scientists and representatives from industry and awards are made on the basis of originality, practicality and potential to enhance productivity.  The USDA would be well advised to apply a similar approach in allocating funds. Unfortunately budgets have to be expended and staff have to create the illusion of productivity, not to mention response to political imperatives which distort rationality and logic.