Quality by Design

When conducting food safety tests, there is little flexibility in the interpretation of or response to results. In most cases, it is either there or it’s not, with limits set in the U.S. by FDA, USDA, or, in the case of pesticides, EPA. However, there are lab processes and practices that can impact these results and challenges which labs face in attaining trustworthy results. Following are 10 tips to help ensure that your lab results are truly resulting in food safety and quality for your products.
 

1. Use lab tests to ensure safety, but don’t expect testing to create safety. For this reason, processors need to design quality into their systems. “You have to build quality into a product, you can’t test it in,” said Janie Dubois, laboratory program manager for the University of Maryland/JIFSAN International Food Safety Training Laboratory (IFSTL). “This is the objective of HACCP in food. You need to look at everything, determine where you should be monitoring, then do it.”
 

2. Test early in the process. “It is extremely expensive to just verify safety at the end of production and not along the way, because at that point, it either needs to be reprocessed or put in the trash,” Dubois said. There are a lot of new tests that can be conducted quickly without a great deal of training. These include such processes as strip tests that can be conducted right on the line; thin films, that need review by an analyst, but not necessarily someone with a Bachelor’s degree in microbiology; and screening tests, which are not the end-all answer, but are inexpensive and can be passed on to the lab for review and confirmation.
 

3. Beware of mistakes. “If you make a mistake, you have a better chance of getting the result you were hoping for,” Dubois said. For example, if a lab tech makes a mistake in preparation for micro testing, it is likely that an extraction would be negative, resulting in a zero count, and showing the product to be within tolerance. On the other hand, if the culture is or becomes contaminated, a false positive could result. And those, Dubois said, are expensive mistakes.
 

4. Monitor the environment. “There’s always inherently more risk when testing finished product,” said Benjamin Pascal, chief business officer for Invisible Sentinel. By regularly testing the environment—then cleaning and/or sanitizing and retesting if needed, you can prevent issues and reduce positive finished product test results. Again, you should have a specific environmental monitoring plan, focused on the how, when, where, and frequency, and have buy-in from and a sense of ownership by all workers. You may be testing, but are you testing raw, post-kill step, finished product? Are you testing the areas of highest risk?

Additionally, “sampling will always be a challenge for every diagnostic,” he said. “How do you find that one bug?” You cannot simply test an area because that is how it always has been done; rather, he said, “There needs to be good logic behind where and how you are testing in the facility.”
 

5. Validate your matrices. When a new product is developed, how do you validate that the test results will be accurate on its matrices? Some products, such as chocolate and spices, are very difficult to test, and any new or redeveloped product needs to have the test validated to ensure it is effectively testing the product and not simply resulting in negatives (real or false) because it isn’t really working on the product. “It is important that we validate that the test truly works,” Pascal said.
 

6. Have a plan. What will you do if a test comes back positive? Pascal asked. You need to be prepared for that, he said. “If we have a positive, here is what we will do, and here is how we will ensure quality.” The plan needs to be well-defined and understood by everyone.

When determining a strategy for action to be taken should a result come back positive, Pascal said, some of the questions to ask include: Is this a high-risk food? Does the process include effective kill steps? How many? Is it sold raw? Eaten raw? “One size doesn’t fit all.” Because of this, she added, “There’s a lot that rests on the shoulders of the analysts and laboratory manager,” Dubois said. “Trust is something you earn.”
 

7. Walk the floor. “I’m a big fan of technical people walking around the plant,” Dubois said. Having a different, technical set of eyes can spot potential contamination issues that may not be noticed by those who work the area every day.
 

8. Provide training and interaction. The mission of IFSTL is to teach fit-for-purpose methods that produce results demonstrating the safety of food products. A key part of this is the interaction opportunities attained by lab analysts during the training, Dubois said. “We have seen that people feel a need for building their network of technical knowledge. People are starved for friends in the industry—someone they can bounce things off of.” Lab managers or workers in larger companies may get the opportunity to go to conferences such as those put on by AOAC, IFT, IAFP, etc., but smaller companies and those in international plants don’t always have this access.
 

9. Speak the same language. One of the greatest challenges that Dubois sees for in-house food labs today is that of multiple labs within a single company caused by its expansion or mergers. As companies get bigger, they have more labs that need to talk with one another, but they don’t always speak the same language. They may be using different equipment, test kits, etc., so even when they talk with each other about the results they attained, they may not be talking about the same thing. Thus when companies merge, or simply communicate from one facility to another, technicians need to ensure they are talking the same language.
 

10. Have a trustworthy data system. If all the above is in place, but the resulting data isn’t retained in a secure system, there could be questions on the final results.

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