Time for Some Listeria Hysteria!

By Guest Author on 29 March 2018

This article is my independent food safety opinion.

I'm not sure about you, but as a food safety professional (and a consumer), I have noted an increased number of reported Listeria incidents in recent years. Over the last year alone, the nasty one: Listeria monocytogenes (Let's call it Mr. LM) has managed to kill over 200 people with sausage (South Africa), melons (Australia) and sweetcorn (Europe/US); and that's not counting the numerous preventive recalls for cheese, ice-cream and other foods.

What concerns me is the fact that Mr. LM is popping up in new food categories that have traditionally not been implicated (ice-cream, vegetables, even dried), which suggests Mr. LM is a growing problem for the food industry. (Admittedly, the micro detection technologies have advanced and outbreaks in the distant past may not have been able to pinpoint the source as effectively. It also doesn't help root cause investigations, that you can get sick (and die) from Mr. LM up to 70 days after eating contaminated food).

So what are your options!? Well, if you are a food producer, the only barrier between you and a major Listeria recall are preventive controls and measures or as I call it: "a Resilient Food Safety System".

To get you started, here are four key lessons from my pathogen traceback involvement in the food industry (note - these lessons are from several different products, companies and factories).

Fix your floors!

Mr LM's favourite hideout is the factory floor. Unfortunately, the number of floors I have seen with pooling water, loose tiles, cracks and lifting is too numerous to count. Building maintenance in the food industry really is the poor cousin of equipment maintenance. I know that replacing floors doesn't make money, but if you have a poor floor and the Listeria family comes knocking, no amount of "deep cleaning" (whatever that means?) will work. You will have to replace the whole floor first!

Clean your Chains!

My visits tend to be anticipated with some nervousness; apparently, I can be scary (I think it's my "Dutch Direct" approach). As I don't believe in unannounced audits (here's my logic on unannounced audits: if you really don't trust your supplier enough, that you feel the need for unannounced audits, I suggest you start looking for a new supplier that you trust!), most of the factories I visit tend to be very shiny. Fortunately, in most cases, all I have to do is to open those shiny stainless steel doors underneath the machine to expose a problem (Yes, I do ask nicely first!). So, it really is worthwhile to inspect the gear underneath your filling lines to ensure those drive chains are clean (they are often close to the floor too!). Oh, and one more thing, I have been told of pathogens found in food grade grease.

Keep it dry!

The Listeria family does not like dry! Fortunately for them, most food operators like to keep their environment nice and wet: hosing the floors, water blasting (perfect to get the family from the floor onto your equipment!) and plenty of condensation. I have seen plants with pretty poor plant access controls from outside, that did not have a Listeria problem. Their saving grace: keeping the plant dry during production! Yes, it's not easy to break the "hosing habit" of food operators, so I often ask them: "Gosh, do you keep your kitchen at home this wet as well?".

Find Them in your Factory!

A good environmental pathogen monitoring programme is worth it's weight in gold! One of the first things I look for during my factory visit is the design and effectivity of the monitoring programme. It's like your pathogen "smoke alarm" and not very difficult to implement. The great news is that with the latest technology, you can get results within less than 24 hours, so you can do something about it straight away.

Of course, there are numerous other risk factors, such as cleaning habits, water circuits etc.; however, if you manage the four points above, Mr. LM will struggle to get a foothold.

And one other thing! Recent research has shown that Mr LM is very close to Listeria Innocua (Let's call it Ms. LI). Turns out, Ms. LI is not as "innocuous" as her name suggests. They appear to be lovers and she hides Mr. LM in the environment, so rather than having a big sigh of relief when you find Ms. LI; increase your vigilance, because Mr. LM will be around somewhere (Maybe we should rename her Ms. LA, like "Listeria alarma").

~ Jack


This article is reproduced with permission from the author.

About the Author
After a variety of leadership roles in the food industry, Jack van der Sanden travelled the world to assess food safety controls in food manufacturing and distribution. All this experience, knowledge and passion enables him to review and strengthen food safety and quality systems in the global food supply chain; a kind of "Food Safety Architect".  Contact him at jack.vds@xtra.co.nz