Written by Jon Kimble and Kyla Ihde, Safe Food Alliance
Is it an FDA requirement or a strong recommendation for environmental monitoring for RTE foods?
In areas where your company is handling product that is 1) considered a ready to eat food, and 2) is exposed to the environment (not entirely contained in a package), the FDA expects you to conduct environmental monitoring. They do not tell you precisely what or how to monitor. It’s up to each food company to determine whether to monitor for specific pathogens, indicator organisms, or both. You are also responsible for developing a sampling schedule for this monitoring (locations, types of samples, frequency). The FDA will also expect to see some associated product testing when you meet the above two conditions. Remember: The greater the risk, the greater the frequency for swabbing.
It is also important to point out the FDA’s definition of ‘ready to eat’ may differ from what you’re thinking. Ready to eat is defined as “any food that is normally eaten in its raw state or any other food, including processed food, for which it is reasonably foreseeable that the food will be eaten without further processing that would significantly minimize biological hazards.” Under this definition, foods like cookie dough are considered ready to eat! We all remember tragic instances when recalls and consumer illnesses took place by consuming raw cookie dough.
More information can be found on FDA Environmental Monitoring at https://www.fda.gov/food/sampling-protect-food-supply/environmental-sampling.
Is it true that if you swab Zone 1, you cannot release a product that runs across the surface until results have been confirmed negative?
Waiting for a negative is highly recommended. We are not aware of a specific regulatory requirement to this effect, but this is the guidance in the industry. If you detect a positive result and release the product, it becomes reportable to the FDA, and you could be facing a recall with evidence of a positive result. The food is considered adulterated. It is simply not worth the huge cost you may face to bring the product back, in addition to damaging your company’s reputation with your customers and potentially hampering future business opportunities.
If you are going to swab a product contact area for an indicator organism like coliform or generic E. coli, we generally recommend that you swab during periods of extended downtime. This approach allows enough time to obtain the laboratory’s test result and for you to take corrective actions before producing the product on that equipment. If you receive a positive result or a result that is out of spec after processing has already begun on the affected equipment, there will be a high cost and product loss or rework.
For non-RTE products that require a customer kill step and do not have a historical pathogen issue, what would you test for? It seems there is not an obvious concern for any specific pathogen.
If your product is not ready to eat, and similar products have not historically had any recalls or pathogen issues, typically the purpose for swabbing is to determine “Is the processing environment clean in general?” In these cases, it’s common to test for indicator organisms to ensure the cleaning and sanitation activities are productive. You may also check the ambient air at strategic times to see it’s contaminated. One of the key benefits of testing for indicator organisms is the results are quantitative, not just a positive/negative result, but instead a numerical value. Having this type of result allows you to trend them over time, to better determine the effectiveness of your sanitation program.
It’s also important to consider the moisture level of your product, the type of processing conducted onsite, and past results from monitoring. Based on these factors, you can better determine which pathogens present the most considerable risk to your product. Typically for low moisture foods produced in a dry facility, you would want to swab for Salmonella, E. coli, and coliform. For wet environments, Listeria is a must, along with other appropriate organisms.
Can you use the same swab for Aerobic Plate Count (APC) and coliforms?
Generally, you would be using a sponge swab in its various forms when swabbing larger areas, and you would use a Q-Tip swab to evaluate niche areas that would be harder to reach with the standard swab. You can use sponge swabs for isolating any organism. The broth provided in your swabs bag is to keep the organism stabilized while being transported. It’s a neutralizing broth that helps ensure an accurate result and avoid a false positive or negative. When taking swabs, typically, indicators can be all taken with the same swab. Meanwhile, pathogens need to have an individual swab for each one.
Is the term “adequate” defined for food processing?
Because food processors vary so much, there is no specific definition of adequate that we can reference. You must judge based on your facility and program what is adequate for the type of samples taken, where, and when.
Do you have to be running your product line to do follow-up swabs?
You can do swabs even if you aren’t running your lines. It may depend on what your food safety certification standard requires. You should check the verbiage they use for environmental monitoring to see what they expect from you and any associated guidance documents for the standard. Besides these requirements, your team should use its best judgment to design an effective program that will help protect the company from risk.
The easiest way, in our opinion, to do follow-up swabbing is on consecutive days. It makes the process go faster. As soon as you have that first negative from your first vector swab, you continue for two more days to get three negative results. However, if your subsequent vector swabs produce a positive result, you should start your vector swabbing again. The goal is to obtain three consecutive negative results. If you encounter positive results in this process, it indicates an issue that requires further investigation into your sanitation regime.
This piece of your program is particular and unique to your facility. We suggest asking a consultant to verify your environmental program to ensure you meet sanitation and certification guidelines. Our organization does provide this service, and we would be happy to give you feedback on your program.
When sampling for three (3) consecutive negative samples after a positive result, do you need to clean the piece of equipment each time before swabbing?
This will depend on how your program is set up. Typically, the area is thoroughly cleaned and quarantined and then swabbed using a radial/starburst pattern from the positive site until 3 negative results have been received. Vector swabbing helps you confirm 1) whether the organism is still there; and 2) if you killed it. You are trying to determine three things: Did you kill it? Did it spread? If it spread, how far?
Cleaning before your daily vector swabs may not allow you to identify an organism is being protected by a biofilm. Some organisms can be found a few days later because of the biofilm protection. Again, this is determined by your program and this is based on the risk to your product.
If I get a positive result in Zone 1 and I have a kill step later in the process, what happens?
There’s no single answer to this question. It comes down to a risk-based decision you have to make as a company based on your product, process, and what you know about them. Keep in mind, be conservative with your approach so you’re not taking any risk that an organism may be present in your product. You don’t want to end up with contamination in the finished product. This question is very situation-specific and would benefit from one on one guidance from a consultant.
Apart from testing, are there other methods of validation for environmental monitoring?
Besides swabbing, other tools in your arsenal for evaluating sanitation efficacy include using visual inspection, and in many cases, odor. However, testing for ATP and microbiological pathogens are the most traditional ways to verify.
To help eliminate risk, most companies use ATP in unison with appropriate microbiological swabbing. ATP swabbing detects the basic unit of energy in all living cells. As the cells grow and respirate, they produce ATP to power themselves. The ATP swabs evaluate general cleanliness; it can help in being a precursor before doing speciation swabbing, which takes longer.
It’s essential to understand the difference between verification and validation. Validation of environmental monitoring is much more than a daily routine activity. Routine activities are considered verification. Validation focuses more on trends over time, using data to determine your ‘baseline’ and if a deviation from that baseline exists. Preforming a single swab is not considered validation. To validate, you need to trend data and look for tendencies or shifts in results.
If you need more help, we have a great article on verification The 6th HACCP Principle: Verification.
Can you please explain more about vector swabbing?
Vector swabbing is a crucial way to ensure that your facility has not been contaminated after finding a positive result. Here’s an example:
Let’s say we are talking about a foot frame on a piece of processing equipment. You’re running the line; people are sweeping and putting everything into the trash. In this instance, you need to think about how an organism can travel. It can travel on shoes, on brooms, on forklifts. If your foot frame or your floor (traffic areas) are positive for a pathogen, that pathogen can potentially spread throughout your entire facility.
Best practices for vector swabbing are to test the area that you got the positive for or presumptive positive, depending on how you do your vector swabbing.
When you get a communication from the lab, they might be referencing the following:
Presumptive Positive – This is when your sample has triggered positive in analysis on a specific instrument (PCR or VIDAS). These are two common platforms used to detect pathogens. Once the pathogen is detected, it is called a presumptive positive. Usually, the lab will send you communication and ask if you want to continue with confirmation (additional steps to verify the instrument’s results).
Confirmed Positive – Once a presumptive positive, confirmation is usually completed using FDA BAM methods. These methods use more rigorous techniques and require additional time depending on the organism, which can be an additional 4 to 5 days.
Because of the confirmation turn-around time, most companies consider a presumptive positive a confirmed positive immediately. Waiting 4 to 5 days allows for a higher risk, especially if there is a lot of activity around the area. This activity has the potential to spread the pathogen throughout your facility.
Is it enough if only a third party sanitation company does ATP, or do you strictly recommend internal ATP along with a third-party company?
We think you should be doing your testing internally, especially if the company swabbing is also responsible for sanitation, as this poses a potential conflict of interest. Suppose you are going to have someone else externally doing your swabbing. In that case, you need to scrutinize their training program and oversee what they are doing regularly.
ATP swabbing is an excellent way for you to internally check before you send out your speciation swabs. It also depends on your operation. In many cases, companies will perform ATP swabbing on their product contact surfaces before beginning production. The best approach needs to be determined by the site. It also depends on your risk, including the products produced, facility historical results, FDA guidance, and certification program requirements. If you are not creating ready to eat foods, you may be able to do just ATP swabbing and make sure you are cleaning your facility correctly. Most companies do ATP swabbing before they send speciation swabs to the lab. If you use this method, it can save you money because you would only be sending swabs that were confirmed by the ATP test.
Keep in mind that it’s not very common for a third party to do ATP testing. We would highly suggest doing it yourself.
What are the best practices when there is a positive hit on a pathogen on the input line but not on the finished product?
If there is a positive pathogen result on the input line, you should assume it’s getting into the product. It is not safe to conclude that if you did not find it in the finished product, it’s not present somewhere in the product or process. A negative test is not enough to tell you the same organism is not present in the finished product. Pathogens are usually distributed sporadically and can be easily missed in sampling.
If you think about how much product you run across that line or through that input and output, and only sample potentially 375 grams (or less) of a 45,000-pound load, statistically, you might miss contamination. You want your actions to be based on scientific information and be data-driven, not based on samples taken. You want to prevent anything from getting into your product before it puts consumers and your company at risk.
One root cause that we continually see leading to recalls is the reliance on one negative. Only one negative does not indicate that the product is safe. We’ve seen companies receive a positive pathogen result and then retest their product until it’s negative. This type of process will not protect your company or your consumers.
What are the limits for APC or TPC on food contact surfaces?
There’s not a single straight forward answer to this question. It depends on your facility and your history. It would be best if you established a baseline for your facility.
A lot of the time, APC swabbing doesn’t give you very much information. Typically, you test APC in conjunction with something else, such as an indicator organism, Coliforms, generic E. coli, Enterobacteriacea. One of the most common test combinations is APC and Enterobacteriacea. The Enterobacteriacea group includes total coliforms and generic E. coli and is a good indicator of contamination.
This combination is popular because it can indicate several different risks. For example, if you get a count on your APC swab but nothing on Enterobacteria testing. That suggests there could be Yeast and Mold on the area, which isn’t a sanitation indicator. Entero also includes Salmonella, another reason many companies use the Entero swabbing in conjunction with APC.
Why is ATP such a big deal when results vary based on the surface being tested?
An ATP threshold can be adjusted based on the surface. If the area you swab tends to be slightly higher in ATP because it’s a raw product, this could be adjusted. But, if you are consistently getting a high result, that also may be telling you the surface is not suited for the operation. The high results could also tell you the surface is not being cleaned frequently or well enough.
It is important to remember these answers are based on assumptions. The best route for your company is to get consulting for your specific product and processes. Our team of experts would be more than happy to assist you with any environmental monitoring questions you may have.
‘Ask us about our Environmental Monitoring Package! Our team of experts can come onsite to provide training or consulting and take swabs all in the same visit.’
