QA. Tyson developed a Niche Buster program; can you explain what it is and what role does it play in food safety?

Roop. Niche Buster is a Tyson coined term for a process we use to pressurize hollow tubing with water to detect defects. Under pressure, we can identify cracks and holes in the equipment which allows us to repair or replace. We regularly rotate through different areas of the facility where hollow tubing is used to ensure no cracks or holes have developed. In addition to pressurizing with water, we are able to flush with detergents or sanitizers. This prevents “niches” from developing and eliminates any harborages that have developed.


In this context, a niche is a small area or place that is ideal for microorganisms to live and thrive. To eliminate them, they are identified, then they are addressed using different methods, depending on the nature of the niche. For example, for hollow tubing: cracks or holes are welded to prevent internal contamination and fittings are added to the top and bottom that will allow regular flushing with detergents and sanitizers to assure organism’s growth is retarded or eliminated. These are considered short-term solutions. The long-term solution is the replacement of the hollow legs with open angle steel that totally eliminates the possibility of niche formation. Other niches could include electrical control panels, interfaces of equipment bolted to the floor, overhead machinery parts, etc. All present unique challenges but can and must be addressed.

QA. Discuss the progression of the program’s use against Listeria in R2E plants to combat O157:H7 cross contamination and other uses?

Roop. Pathogens enter the food chain in many different ways. They can come in with the animal and end up on the meat as result of cross contamination from hides or feathers. They can also enter via cross contamination from handling by workers or equipment during dressing or cut-up processes. The principles are the same regardless of the organism. The challenge is assuring that the product does not come into contact with contaminated work surfaces, gloves, water, hides, etc.

QA. What are your “seek and destroy” environmental monitoring practices?

Roop. The Sentinel Site Program is an environmental monitoring program designed to alert our teams that there is a potential for Listeria spp. harborage (niche) that may lead to product contamination. Each plant team is instructed by corporate food safety and quality assurance to swab randomly selected and targeted sites on each line or area used to produce or convey fully cooked products each week. These swabs are sent to one of Tyson’s corporate laboratories and evaluated for the presence of any of multiple species of Listeria. These data drive a “seek and destroy” management philosophy predicated on the concept of finding and fixing sources of potential contamination before food safety is compromised.

If bacteria belonging to the genus Listeria are found, the plant team convenes, evaluates the area and all records associated with the positive sample, and determines potential sources of contamination. Additional investigatory swabs are collected prior to implementation of corrective actions to determine the sanitary status of the areas surrounding the initial positive.

The results of these swabs serve to confirm or refute the existence of transitory or random contamination or a harborage situation. The team is then required to demonstrate that its corrective actions have been effective by swabbing that same site three times each day for three successive production days, resulting in nine consecutive negative results (a statistical analysis based upon the assumptions made by the authors of the “Draft FSIS Risk Assessment for Listeria in Ready-to-eat Meat and Poultry Products” [FSIS, 2003] which determined that there is an extremely low probability of getting nine consecutive negative swab results if there are viable Listeria spp. remaining on the surface of the swabbed equipment). If any additional positives are noted during this follow-up sampling, the program escalates to require additional actions up to and including implementation of a CCP for the control of Lm and finished product testing on a test-and-hold basis.

QA. Tyson has elected to share this program with the industry and it has been recognized by USDA. Why?

Roop. Tyson’s technical team shares the Sentinel Site Program with representatives of any interested manufacturer, customer, regulator or NGO upon request. Several industry peers have used the program in their own systems to monitor and reduce Listeria spp. contamination in ready-to-eat food-production facilities. It is recognized by USDA by name in an appendix to the current “FSIS Compliance Guideline for the Control of Listeria monocytogenes in RTE Products.” With each revision to the program (currently operating under version 16), we meet face-to-face with our regulatory partners in Washington, D.C., and at the district/regional level to share the changes/improvements and provide the opportunity for questions and correlation. This dialogue provides the opportunity for regulatory authorities to understand how the program works, the intent of the “seek and destroy” approach, and the commitment that the Tyson Foods’ management team has to ensuring the safety of RTE products.

QA. How does this fit in with FSMA’s environmental monitoring requirements?

Roop. The Sentinel Site Program is used as a verification of our overall sanitation program which is a preventive control in the hazard analysis and risk-based preventive controls (HARPC) plan.

QA. You also have a Total N60 Program that has been recognized by USDA and adopted by other food companies, correct?

Roop. Yes. Tyson N60 was developed as a sampling program for beef products intended for raw ground use and it was based on three principles: targeting of surface tissue where the organism will be present; a statistically based sampling plan [e.g., 60 pieces] to ensure >95% confidence of detection; and a laboratory methodology that is capable of detecting extremely low levels of contamination. USDA adopted the N60 method for its own verification program nationwide. USDA/AMS uses N60 as a sampling program for school lunch product. The vast majority of U.S. beef producers use sampling methods based on Tyson N60 principles.

QA. What else does Tyson do for environmental monitoring? How are the results verified/validated?

Roop. We use ATP swabs, visual/tactile, GMP monitoring, APC swabs, and for a limited number of product categories, we include the species of Salmonella in our environmental monitoring, etc. Verification and validation of the results depend on three primary factors: statistical analyses of the data that derive from microbiological monitoring; auditing of sanitation execution and equipment design and maintenance; and routine finished product testing for the presence of Lm.

QA. How do all these work together to provide food safety?

Roop. These programs demonstrate to our team that we are committed to systematic, continuous improvement in food safety. This awareness improves our food safety culture, so, in essence, it results in an endless loop of improvement.

QA. Why is environmental monitoring so important to Tyson, and to the food industry as a whole?

Roop. The “seek and destroy” philosophy of finding and fixing potential sources of product contamination is a cornerstone of the food safety commitment at Tyson Foods. In order to find problems, one must aggressively look for problems. This philosophy is based upon the belief that finding a problem is not an indication of failure – rather, finding a problem represents a success, as it allows us to learn and improve our processes. As we have established over the past two decades in discussions with representatives of both FDA and FSIS, the key to regulatory compliance is not demonstrating all negative monitoring results. Rather, compliance is indicated by the effectiveness of corrective actions in response to positive swab results. The species of Listeria are ubiquitous in the environment and a food plant is a complex environment. Lm is usually found in any food-production facility. If positive swab results are never obtained in a production environment, it means the management team may not be looking hard enough or may be using the wrong tools. Improvements are made, not when you expect zero, but when you expect continuous improvement.

QA. What other comments or recommendations would you have for the food industry in relation to environmental monitoring?

Roop. Given the previous comments about the ubiquitous presence of Lm in the environment and the frequency of its presence in food facilities, we believe it is important to extend food safety-control measures beyond the physical plant, equipment, team-member practices, and environmental monitoring.

We strongly support that refrigerated, ready-to-eat products have a natural characteristic that inhibits Lm proliferation in the product during its shelf life (e.g. high-acid levels in fermented meats or low-water activity in baked goods) or the product be formulated with an ingredient that has been validated to prevent proliferation of Lm in the product.

The author is Editor of QA magazine. She can be reached at llupo@gie.net.