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    Product Testing, Part 2: Produce Perishability and the Need for Speed

    Tuesday, December 21st, 2010

    Julia Stewart:
    Hello, this is PMA PR Director Julia Stewart, and welcome back to PMA’s audio blog, “Ask Dr. Bob” with PMA’s Chief Science & Technology Officer Dr. Bob Whitaker. In the last post we introduced the issue of product testing and Bob promised to share with us some of the issues, challenges and opportunities surrounding this “hot” topic for our industry. In this post, we’re going to talk about the challenge posed by the very thing that makes our products so special: freshness. Bob, why isn’t testing fresh produce just like testing, I don’t know, let’s say canned soup?

    Julia, as a food category, produce is unique because of its perishability. We don’t have the luxury of being able to hold products like companies who make shelf-stable foods. In our case, failing to get most of our products to market as quickly as possible has product quality implications – and that can cause product to be refused and sales to be lost.  It’s critical for crops to be harvested, cooled, packed and shipped as quickly as possible to preserve quality.

    Indeed our whole logistics chain is built around that premise, and we pride ourselves on getting product to market quickly. Likewise, consumers and buyers value this speed because it means they will receive the highest quality, freshest product possible.  Many buyers today demand products be shipped within 24 to 48 hours after harvest – and in the case of processed products, often demand same-day-as-processed shipments.  However, as buyers increasingly request finished-product testing in some commodities, the industry has struggled to find workable programs that accomplish both testing and shipping requirements.  This is principally because of the time required to sample, transport the sample to a lab, process the sample for testing, perform the test and communicate the test results before product can be released to the marketplace. “Test and hold” programs have proven difficult to implement in our industry unless buyers are willing to give up some shelf life to permit the 24 to 48 hours it typically takes to conduct testing using today’s testing methods.  Our industry is rife with stories of operators who’ve faced some very difficult challenges as a result of not fully understanding the implications of setting up product testing programs. So it is critically important to think through the ramifications of product testing.

    But Bob, although government does not require testing right now, and that may change, in some cases not testing product is not a real choice since the testing is driven by buyers, as a condition of sale in the marketplace. So what can industry members really do?

    Well Julia, you have to have a plan.  Let’s face it, in recent years we have seen companies perform recalls based on initial test results that were not confirmed, we’ve seen recalls initiated based on faulty lab practices that led to inaccurate tests, and we’ve even seen cases where products were placed on hold due to a positive test result but were mistakenly shipped anyway so that they had to be recalled after the mistake was discovered. 

    We have also seen the pressures of delivering an order resulting in folks sending out the product while still waiting for the test results to come back from the lab.  That’s a very risky approach which sometimes has resulted in product having to then be withdrawn or recalled when positive tests are found and the affected product has to be removed from the market.  Similarly, we have seen suppliers struggle when they hold finished products in a warehouse waiting for the test results to come in.  The day or two it takes to get the data back from a lab means the shipper has to store the product longer which has an expense associated with it.  It also highlights the fact that the shelf life clock is ticking – that’s another day or two worth of shelf life shaved off the product.  Another way of looking at it is that it’s also another day or two worth of freshness lost.    And not to be glib, but that’s when everything works well and the result of the test is “negative”.  If a positive test is determined, confirmation testing can take another 48 -72 hours beyond the initial test rendering the product all but useless if it’s subsequently shown to be pathogen-free. 

    It’s a real challenge and a very delicate balance.  Unfortunately we’re out of time for now. Bob, in our next post I’d like you to explain a bit more of exactly how one can go about making a decision on product testing issues. So listeners, be sure not to miss that one! Until next time.

    Product Testing, Part 1: Smart Investment or Not? An Introduction

    Tuesday, December 14th, 2010

    Julia Stewart:
    Hello, this is PMA PR Director Julia Stewart, and welcome back to PMA’s audio blog, “Ask Dr. Bob” with PMA’s Chief Science & Technology Officer Dr. Bob Whitaker. Bob, microbiological or pathogen testing is getting a lot of attention right now. How come? And, why should we be concerned about it?

    Well, Julia, microbiological testing is nothing new to our industry. Growers and processors have been doing micro-testing for quite a while.  Typically it’s been employed to monitor sanitation efficiencies, to determine the quality of irrigation water, and in product development applications to monitor various aspects of shelf life. 

    But because of recent high profile foodborne illness outbreaks, the produce industry is facing increasing pressure to better safeguard our products.  So we have seen increased implementation of Good Agricultural Practices programs in the field, HACCP food safety programs in our processing operations, and even commodity-specific food safety programs for certain commodities that FDA considers high risk.  In recent years we’ve also seen a significant increase in the number of surveillance-driven product testing programs conducted by various government agencies, mostly focused on testing for Salmonella and E. coli O157:H7 in select commodities. 

    We also have FDA testing product at the border, in mobile lab deployments, as part of facility inspections and at distribution points.  And, we have USDA through its microbiological data collection program conducting market-basket testing programs, using state labs as contractors to do the testing. Additionally, we have seen increased demands from some buyers for some form of pathogen testing in raw and finished products.  Now, FDA is in the process of developing the produce food safety rule and we all expect some form of microbial testing mandated as a way to measure the effectiveness of potential preventive controls.  All of these activities have resulted in microbial testing and specifically product testing becoming a very “hot” topic for our industry.

    So, since product testing has a long history as part of food safety protocols, what’s the issue?

    Both technical challenges as well as the complex nature of our industry make it a thorny issue to address, Julia. Many other food industries can test raw or finished products with a very high level of certainty that they can rely on those tests to determine whether their products are free of contamination.  It would be great to envision a world where product testing could be done with confidence for various produce items so that we’d know that they were absolutely pathogen-free.  But that’s not currently our reality – because our products are so diverse, we don’t manufacture in a controlled environment, and we don’t have access to a kill step. Produce items are chemically complex and the frequency and level of pathogen contamination is proving to be exceedingly low.  This makes pathogen detection extremely difficult with current technology.  Devising statistically significant product sampling programs is also problematic owing to the non-uniform nature of natural contamination events and the scope of production.

    So, while product testing can be part of a fresh produce food safety program, it should never be considered the “be all, end all.”  Julia, you just can’t test your way to product safety. 

    So, Bob, what then should a PMA member know about product testing?

    Well, Julia, first and foremost, you have to think of product testing as a part of your food safety program; not as your food safety program.  GAPs, risk management, HACCP, sanitation practices, employee hygiene, and traceability are all key attributes of a food safety program. Microbial testing is a tool you can employ to some extent to help measure the effectiveness of these foundation programs. 

    With product testing specifically, there are several tricky areas our listeners need to consider to make informed decisions. These include:

    • the challenges posed by produce due to its perishable and complex chemical and biological nature;
    • the many factors to consider when deciding if you should test raw or finished products;
    • the fact that not all pathogens – or tests – are created equal; and,
    • the challenges surrounding product sampling.

    You know, I don’t want to sound like I am raising these issues as a way to discourage product testing completely.  In some ways, today’s pathogen testing issues are similar to pesticide residue testing 30 years ago. Back then, testing and sampling methodologies weren’t adequate, tests were expensive, and supply chain interruptions occurred. However, pressure from the marketplace spurred innovation, and today sampling practices are standardized, tests are incredibly sensitive, and supply chain disruptions are minimal owing to improved technology. It’s likely that current public and private demands for product testing will drive innovation and hopefully address these challenges I’ve mentioned, eventually resulting in improvements in our current state.  But, it is also fair to say that we have a ways to go and some very real issues with product testing that are causing difficulties for our industry today.

    Thanks Bob.  I know you spend a great deal of time working with our members, food safety researchers and regulators on this issue and I’m happy we’ll be able to spend some time talking about all these challenging areas. However, I’ll tell you now, when we get to the end of this series, I want to know your final thoughts; is product testing a smart investment, or no?

    OK, Julia.  I look forward to that.

    Listeners, be sure to join us next time when we’ll tackle that first topic, the challenges posed by the perishable and complex nature of produce.   As always, you can contact Dr. Bob via email at askdrbob@pma.com. In addition to listening to these and other Ask Dr. Bob blog posts, we invite PMA members to visit our new online Food Safety Resource Center on PMA.com. We are regularly posting new food safety content there to help you meet your company’s food safety needs.

    Thanks for joining us today.