Transcript: Managing Listeria in ready-to-eat food production
Introduction
Hello everybody. So, my plan today really is to just give a quick overview of Sofina and what we do, to explain how Listeria impacts us, and then to just pick out some key areas of our Listeria monitoring programme that we have on our sites that might be of interest, and dig into them a little – just to give a bit of extra information on how we control it in our operations across the different Sofina sites.
And then how we are intending to comply with the upcoming change, and just some general advice on how we handle it at site level.
Sofina Foods
So, Sofina Foods has been around for 30 years. It is owned by Michael Latifi, and he started in Canada with poultry sites. He has expanded from Canada across the UK, Ireland, and the EU, and currently has 23 sites in Europe and in the UK.
For the most part, we are poultry and pork – there is some level of beef – and we have a number of sites which create ready-to-eat sliced meats for both food service and the retail industry. We also have a number of sites that produce ready-to-eat fish and seafood.
So this is just a quick map of Sofina, so it makes a bit more sense. Focusing in on the Irish side of things, we have sites in Tipperary, in Offaly, up in Cookstown, and over in our new sites that were acquired in Finnebrogue, County Down. Of those, we have ready-to-eat sliced cooked meats in the Tullamore site, which was previously known as Carroll's Cuisine.
So, from a business overview, we have our sliced cooked meats. We do both modified atmosphere and vacuum products.
Where our risk would be mostly generated is our exposure prior to packing. So post-lethality, post-cook, we do a lot of work – whether it would be with glazing, or with crumbing, slicing, and then packing into modified atmosphere packaging or vacuum pack for the consumer. So we have that exposure in our process that could lead to a cross-contamination or a post-cook contamination of product.
Product then goes either direct-to-consumer – so for retailers – and we produce into a number of different retailers in Ireland and the UK, and we also produce for food service, for deli counters, across Ireland and the UK as well.
Listeria control: food safety management system
So, our approach in Sofina to Listeria control is firmly footed in the food safety management system under HACCP principles.
Starting with our prerequisites – so starting with a solid foundation in the basics, I guess – and making sure that our systems are in place.
And then overall, the system is based on risk, which we verify with management review. I haven't put all the prereqs down here, I've just picked out a few that we're going to focus on through the presentation. The main one really, from a risk rating, is going to be around the hygiene, the zoning, our validated cleaning, and the building and fabrication being key as well.
Site layout and zoning
From a site layout and zoning perspective, segregation is key. For the Sofina sites, we are lucky enough to have very clear segregation between our high-risk and low-risk areas. We have full barriers between these areas, which leads us then to control how we move between these areas, and how we move our people and material flows in these areas.
The map is very small, but what I'm trying to demonstrate there is our key areas and our key barriers between our zones. The key areas may be as simple as a double oven with two doors, so we are controlling the movement between high and low by having dual-door ovens.
Or maybe looking at things like the waste and water flows, which is key. So, do we understand our drains? Do we understand the flow of our drains? If there was an issue, are we very clear on what routes to follow when we're investigating, and making sure that that water and the water flow in the drains only moves from high risk to low risk, and not the other way around?
Barrier integrity
A a key part to our management system and our programmes is the assessment of our barrier integrity across our sites. We do this in all our sites by checking our potential points of ingress – areas where staff may move between high-risk and low-risk zones if they didn't have, for example, individual changing rooms or dedicated transfer points.
So, things to consider when you're looking at this may be something like your racks from post-cooking. How do you get your racks back into low risk? Do you have a transfer point? Is it controlled? Is it one way only?
Building that barrier integrity risk assessment – considering all of those points, whether it be the drains, the staff movement, the equipment – is your equipment dedicated just to your high-risk area, or do you intend to move it, and then how do you go about moving it?
Right down to that drain flow again – your air, your positive pressure – all needs to be risk assessed and documented into your food safety management system, which you can then review to make sure that your controls are in place, and that your hazards are managed as you're running them through production.
From a GMP and hygiene perspective, this also needs to be considered. When we're looking at this, we're considering things like: are hygiene staff moving between low risk and high risk during cleaning? Do we have dedicated hygiene equipment? Are we intending to move it between high risk and low risk, or keep it in a dedicated area?
Staff movement and training of staff being absolutely key – that even after hours, we're not moving our staff, and we're using our changing rooms, and keeping our high-risk area high-risk, and not breaking those barriers for hygiene.
That barrier risk assessment in the Sofina sites is reviewed monthly, and forms part of our internal audit system to make sure that these barriers are in place, and the egress routes are controlled.
Building and fabrication
So, from a building and fabrication perspective, again, we're just dealing with our basics, our prerequisites.
We're going to look at our walls, our floors, and our equipment. So for our sliced cooked meats, some of our key lines are going to have slicing and packing equipment.
Some key areas to consider when we're looking at our hygiene assessments or even our controls in place – we do need to consider harborage, and areas where we may find a build-up or a source – that you may find some standing water. So, things like slicing blades, behind the slicing blades, looking at things like behind panels – panels that maybe wouldn't be opened on a regular basis as part of your regular cleaning programme, maybe a deep clean.
So the design of your equipment – again, fundamentals of your prerequisite programme – need to be considered there, and as you're moving through your environmental monitoring programme and your assessment of it, it's good to look into all of these pieces of kit and check: is there areas for harborage on this equipment? Are they properly made? Is the material they're made of smooth, stainless steel, easy to clean?
That applies too to the wider room itself. The floors and walls – so are we considering that the floors and walls are sealed properly?
Is there flashing on the walls that perhaps water or debris could get down behind, causing a harborage issue in the walls?
And again, with floors – is the floor sound? Is it smooth? Is the seal of the wall and floor good, where you're not going to get a harborage?
With your floors specifically – are they draining? Are they leaning to drain, so you're not getting pooling water?
If you have pooling water, then you need to consider that you may have staff, racks, and product running through that area, which could lead to a cross-contamination.
So, overall, as you're building your risk assessment, there is a fundamental in your prerequisites that you can step-by-step build into your monitoring programme and how you approach your controls that you're going to put in place.
Just even to note things like welded joints with no hollow sections – whether that be on the side of a piece of equipment. Welding can be one of the major harborage points that you could find on a piece of kit, where you may have had a repair or a temporary repair that wasn't to standard and could form a point where you could have some Listeria harborage.
Listeria, once it gets in, can persist. Which is where our barriers and our controls are key to keeping it at bay. So our hygiene team, their training, and then the verification and validation of our cleaning is absolutely key to our controls.
With that, again, you need to assess your day-to-day cleaning – so most people would look at their general cleaning of their machines and equipment – and then you need to look at your wider cleaning, your cleaning of things like your fans, your cooler units, your walls, where while they won't be direct food contact, they could form a point of harbour.
You may get cross-contamination from the cleaning of your lines to your walls, so it does need to be a full consideration of the room as well as your kit, as you're working through your controls and your hygiene controls.
There are a number of chemical suppliers who will work with sites to build very good hygiene programmes, and to build key inspection points into each of those cleaning procedures, which can be very beneficial as well.
Environmental monitoring programme
So then, from our environmental monitoring programme – as Mary mentioned earlier, we have Guidance Note 45, which is an excellent resource to build on the zoning, the risk-based swabbing, the trending and escalation of procedures, and what to do if you find Listeria either in your site, food contact or non-food contact.
A robust monitoring programme will give you an early warning system. If you have a system in place where you're getting swabs, you may get a positive in a drain - you're one step away from your product, which means you have an option then to build in detection. Your reaction and your CAPA to that can protect your food and protect your finished product.
So, for example, if you found, while it's not food contact, it allows you then to activate your CAPA system, which may be some kind of starburst swabbing where you move out from that drain. You may follow your drain, and then test further points down that drain system to see if it has flowed down the drain.
But again, it's one step back from the product and can really help with controlling Listeria at site level before there's any impact on the food itself.
Working with the Listeria monitoring programme, working with your prereqs, you can build a hurdle approach to the monitoring and to the control of Listeria. Your hurdle approach will include both the product itself and the environment in which it's being produced.
Hurdle approach
This is just a visual demo of the extrinsic and intrinsic factors for control of Listeria – so again, a multiple hurdle approach.
On the left-hand side, you have your lethality steps – so your cooking, your chill controls, your environment – so a clean environment, hygienic environment – right up to things like how you pack, is it MAP, what gases you use.
That can then be combined with your intrinsic factors – so your pH, your water activity, whether or not you've used salt as a component, whether or not you've used curing agents as a component – and that should build you a wider picture of understanding your process, and then understanding your product.
With things like your pH and your water activity, that can feed nicely into the ComBase predictors that Mary mentioned earlier, which you can use as a tool to understand if Listeria, if present, will grow or will not grow.
Use of Combase as a Listeria hurdle
So, predictive modelling is assessing your growth potential. On the next slide, I've just put in a little example of ComBase. ComBase can be a little bit confusing to use, as it has a number of different options as you're working through it.
You need to consider your pH, you need to consider your temperature and your time, again, as part of your multiple hurdle approach.
So, with the product, understanding your product, you're then going to take your worst case. So, again, multiple sampling will help with this, because you can have process variability as you go.
So, if you look at your product – in this case, we're saying that we looked at a modified atmosphere packed sliced ham.
We're going to give it a 14-day shelf life and a storage of between 4 and 8 degrees.
Once it's cooked, we have a pH, our water activity, a temperature – so we have a set of basic items that we can work with, to feed into the ComBase predictor to see if growth is possible.
As there are different ways of looking at this, one of the key pieces for me would be to look at the variance of what you're doing. So, for example, there is natural process variation in making any ham or any poultry products, so it may be worth testing your pH and your water activity over maybe 2, 3, or 4 different cook runs to see what your worst case is for pH and water activity, and use those.
From a temperature perspective – when you're looking at the new legislation, we're considering not just what's in our control, but right through to the end of life in the hands of the consumer.
So ComBase has an advantage where it can look at – as do most predictive models, apologies – where you can put in a dynamic temperature profile. So you could consider your own controls as being less than 4 degrees until it gets to the retailer. You could then put in a slightly higher temperature to allow a mimic of the retailer fridges.
You can also then maybe put in a spike of 1 hour of 18 to 20 degrees – so again, mimicking a customer bringing that home in the boot of their car to get it to their fridge – and then finish with 8 degrees, which would be considered the average temperature for a consumer fridge. So it allows you to consider worst case all the way along the way, as you are working through it.
Again, once you have all your information gone in, you put in the time that's there, and it will give you a prediction as to whether it will or will not grow, based on the information that you have fed into it.
Once you've considered your variables, then it's worth considering WIP life. So it's one of the things that within a food business, cooking to slicing and out to the consumer, there may be a lag time there of two days day, a week, depending on the product you produce. So using a predictive model, it wouldn't be complete if you didn't consider that time where you have a WIP life in the factory. Again, depending on your product, could be a day, a week, a month.
And that would need to be fed in as part of the ComBase prediction to give you an accurate picture of what you're doing.
Understand your product and process
To loop back then, understanding your product and your process is key. Once you have your prerequisite programme in place, your fundamentals are there. You need to understand your process and your process variabilities.
So, using your HACCP approach, looking at your process flow diagrams – which every site has – to understand at each step of the way, where is your risk. So, for example, at raw material intake – you know, have you got solid suppliers? Was the temperature okay? Do you have controls in place?
With processing on the low risk side – are you allowing for process variation? Is your recipe controlled? Can there be variabilities there in temperature or in the life parameters of your raw material coming in?
From a cook perspective – have you hit your thermal process? Have you hit your lethality rates?
Same with the cool – have you cooled in time? Have you controlled your cooling methods?
And then, for this description, I've described it as feedstrap stripped – so that would be a log where we've stripped off the plastic. But again, that might just be opening your product to prepare it for the next stage of processing. What are your risks there? How long do you leave it open? What's your WIP life?
Then into your slicing and packing – what's your production days that you're giving it?
And then allowing for that real-life handling once it leaves your control, and it's out in the retail environment and with the customer.
Be clear on your corrective actions
Again, this just loops back a little bit to what Mary said earlier, and it's my last slide, is being clear on your corrective actions. Guidance Note 45 is a great help here. Actions will differ whether it's food contact or non-food contact, whether it's product or environment. And every site needs to be very, very clear on what they will do in the event of a finding, in the event of a singular or a multiple finding. And it's having that understanding of your process, your prereqs, understanding your flows, your people – that will guide you then towards your actions in your CAPA, depending on where or what you find.
Q&A
For a small food business, what examples would you recommend for gathering physicochemical data?
Mary Lenehan, FSAI: It depends on your product. For example, a pH meter – I think a lot of food businesses might be able to purchase a pH meter themselves, and be trained on how to use that, and just make sure they calibrate that properly, and they could test the pH at the end of every batch if they wanted, and build up that profile.
For water activity, it's a little more tricky, so you could buy a water activity meter in-house and be trained how to use that, but I believe it's a little bit more tricky than a pH meter.
A lot of the commercial labs will do physicochemical tests as well as microbiological tests or chemical tests.
I think those are two good ones to start with, but also, looking at your product itself – if you're using a preservative, some of the models will allow you to put in use of a preservative, and you can see that effect. But of course, you need to comply with any legislation if there are upper limits for the use of particular preservatives, such as nitrate.
Catherine Coady, Sofina Foods: I think that most labs now will give pH and water activity as standard if you even want to do a basic nutritional to cover off your salt and your preservatives as well. But while it may be costly, it's certainly the easier option, I would think, to send it externally.
Is it an issue if a food business isn't using pH and water activity as part of shelf life studies or routine monitoring?
Mary Lenehan, FSAI: In terms of the more holistic approach to shelf-life studies – not just determining shelf life just for Listeria monocytogenes – it is advisable for food businesses and best practice to understand their product in terms of the pH and the water activity, and just really understanding how pathogens might grow in that product and what the profile is.
For Listeria monocytogenes, I would say it's critical to understand that, but depending on the product, you might decide it's more critical to do some other testing – in terms of maybe the salt content or whatever. I think it's very case-by-case, depends on the product, and if you do a little bit of research to understand your product and what are the things that you need to characterise.
And that EU guidance is also a good resource to read around that.
Will there be any testing done on products between leaving the factory and the end of shelf life, i.e. the monitoring gap?
Mary Lenehan, FSAI: In terms of official controls, a certain amount of samples are tested under official controls in Ireland, so obviously not every sample is tested, but they do it on a risk basis. And every year we do a national survey, and there'll be a topic of interest, and a survey sample selected.
So last year, we did ready-to-eat sandwiches and salads, and that report will be published probably next year.
And then also, a lot of food businesses have agreements with their customers, so there will be testing done in accordance with that. And maybe Catherine probably would have more experience in this area.
Catherine Coady, Sofina Foods: That's a very good point. From the retailer perspective, they've been slightly ahead of the curve with this – so a number of the retailers would have us, even on our shelf life testing, testing in triplicate, but with Listeria testing right through to the very, very end. One in particular – or two in particular – would call it a 20% over. So if we're giving a certain shelf life, we would be testing based on our commitment to them, Listeria, right to the very end. So, still working to the not detected in 25 grams, but working it right through our shelf life to the very end.
Do you do CCTV surveys on drains annually? Do any external specialists monitor the internal drains, or is it done in-house?
Catherine Coady, Sofina Foods: We do do CCTV drain surveys annually. That's quite new – we've only done that in the last 2 years across all the sites – and our swabbing schedules for our drains are done internally.
We do a wide range, they are done during production as well. So, our drain swabs are always done during production. There are some different options if you were concerned about your drain – about things like drag swabs, where you leave the swab down for the duration of the day to get a really good picture overall. But specifically for that question, yes, we do, but internal for our swabs, which are then sent to the lab for testing.
Do you take Listeria monocytogenes environmental samples of product contact surfaces, and areas very close to the product contact surfaces during production?
Catherine Coady, Sofina Foods: Yes, all our samples – all our Listeria swabs – are taken during production. So, whether that's food contact, non-food contact, and drain, yes.
What is the difference between absence in 25 grams versus less than 100 CFU per gram?
Mary Lenehan, FSAI: In terms of the method, there are two different criteria for Category 1.2, and one is the 100 CFU per gram. And that is a quantitative test, and it's less sensitive. So that's where the food product is added to a diluent, and then that's plated onto a special agar, and the laboratory will count how many Listeria are in that particular product per 25 grams.
For the detection method, a portion of the food is taken and put into a special buffer, and that will enrich that product, and it will help any injured Listeria monocytogenes to grow and recover, also maybe other Listeria species. And then it's a qualitative test, so it will say if Listeria is detected in that food portion or not.
And as Catherine had mentioned, the test is for Listeria species, so it is important that your laboratory determines if that Listeria is monocytogenes or not. Only Listeria monocytogenes is considered to be pathogenic, and that's why only Listeria monocytogenes is featured in that microbiological criteria.
Then, in terms of deciding which criteria a food business needs to comply with – really it's around whether you have that evidence to show that Listeria monocytogenes, if it's in your product, will grow beyond 100 CFU per gram or not.
So if you can show it, and you've got evidence that's presented to your competent authority and they accept that evidence, you can use that 100 CFU per gram limit. And if not, you're defaulting back to that not detected in 25 grams limit.
The EU guidance explains it in a lot of detail, and there's a decision tree there as well around which criteria is more appropriate to use.
What advice you would have for supplier control when raw material can naturally have Listeria monocytogenes present?
Mary Lenehan, FSAI: So I would say – characterising the risk associated with those raw materials is important. If you have a material that you know is more likely to be contaminated with Listeria monocytogenes, one option could be to use that at the end of the production day. So, if you use it at the start of the production day, you're risking cross-contaminating anything that you make after that.
If you use it at the end of the day, then you can do your full clean-down.
And maybe you would also build it into your verification programme for sampling, so you might be testing raw materials, maybe looking at your actual supplier – are there certain suppliers where you're more likely to get that product contaminated than others?
Catherine Coady, Sofina Foods: I think the other things you could possibly consider as well is what your plan is for that product – what's your process? So, are you looking at a chlorination step? Do you have something that may assist in reducing that risk? Are you considering UV? Is there a lethality step? Are you cooking it? Will that reduce the risk?
I think if you have something that's inherent, and you don't have a process that can guarantee to remove it, absolutely – it's all about your timing then, about doing it last, making sure that you're not cross-contaminating the rest of the product that's going through that system, and then your sampling. Is positive release realistic? Can you do that? Would that help control and not release it then out to the public?
It also comes back then to the whole piece around – can you prove that it's not going to grow?
So, if a site identifies a persistent environmental Listeria issue, should whole genome sequencing be used as part of a root cause analysis approach? And if it is, how would you communicate these findings to the competent authority?
Mary Lenehan, FSAI: I think whole genome sequencing can be a really useful tool for a food business to understand the profile of the Listeria monocytogenes. There might be multiple strains circulating in their business if they have a persistent problem.
You can get strains that are persistent to the factory and maybe have been there over a long period of time, or you might get transient strains that maybe are coming in with a raw material, and they're appearing intermittently, for example. I think it can also really help the food business to tie in with their environmental monitoring programme.
And that's part of their root cause analysis, to understand what strains are particularly associated with maybe different parts of the operation – maybe in terms of equipment or drains, for example, or sometimes what happens is a food business might find Listeria monocytogenes in a drain, and then it's in a product, and they jump to the conclusion that it's come from the drain, but actually whole genome sequencing can show that the strain in the product is different to the one in the drain, and actually there's another strain that's coming from somewhere else.
So it can really assist the food business to understand the profile. In terms of communicating that with the competent authority – if you find Listeria monocytogenes in your product, and it's a breach, you're obliged to inform the competent authority anyway.
But I think the competent authorities – a lot of food businesses we've worked with, and with the National Reference Laboratory – it's becoming more commonplace to use whole genome sequencing to assist investigations, and I would just see it as another tool that can really help food businesses understand what's going on.
Catherine Coady, Sofina Foods: I think everything that you said – we have used it in the past, and I think that piece is absolutely accurate about the red herring, where people assume the drain is the natural source, so it must be the same as what's in the product, and we found exactly that – that when we dug into it, it wasn't.
And I think, from the competent authority piece as well – depending on whether you're under the FSAI or under the Department of Agriculture – it's about working closely with your assigned person, whether that be a veterinary inspector or an EHO.
It has to be reported anyway. There has been some work done with Teagasc in the past as well about sequencing of organisms that naturally occur in something like a potato salad or in veg. There is a good bit of work behind it as well, which, put with your own sequencing, could give you a very good guide as to what you're finding, but it is an excellent tool, and will very much rule in or rule out a source as well.
Control of Listeria in the cleaning process – are there any particular types of cleaning product anyone would recommend?
Catherine Coady, Sofina Foods: Depending on what supplier you use, most chemical suppliers will help you really build that robust cleaning programme in the background. Some will even give you templates for how to validate your cleaning. From a Listeria-specific perspective, I would say in a high-risk environment, you'd want to be fogging anyway, whether you're just using a standard sanitiser. If you have an issue, something like a peracetic acid-based chemical, a fogging chemical, where it can get right in there, and then chlorine tabs in your drains and things like that. But honestly, the chemical suppliers are best placed to advise and do provide excellent advice for control of Listeria monocytogenes in the environment.
What are the implications for the retail sector of the new EU regulations on Listeria monocytogenes?
Mary Lenehan, FSAI: A lot of retailers already had this more stringent criteria in place in their customer specifications anyway, working with their suppliers and making sure that they're prepared for this legislation change. I have been talking to FSAI – we have a Retail Forum, I presented at that, and I'm presenting at the Foodservice Forum on Thursday for retailers to understand the requirements. And we may have some non-compliance if a more sensitive test is used, and some food businesses are not ready for that.
But I think the best thing is really to be working with their suppliers and making sure they're doing everything that they can to control Listeria in their business.
How do the new regs apply to a ready-to-reheat product that is sold solely to other food business operators, which would have their own food safety management system?
Mary Lenehan, FSAI: urrently, a product that is ready to reheat – that has full cooking instructions – is considered to be a non-ready-to-heat product. It doesn't come under the Regulation 2073 microbiological criteria. But that said, there is an obligation on every food business to understand the risks associated with the food that they produce, and to produce safe food.
We’ve seen from last year's outbreak that, you know, for some of these products, even though they were labelled to be fully cooked or fully reheated, we did have some issues, and we ended up having 9 cases, and unfortunately, one of those was a fatality. So to understand the risk profile again for your product – if you're selling business to business, I would say the risk is lower - that food business that you sell to should have a food safety management system that they follow in terms of making sure that product is fully reheated.
And Listeria monocytogenes will be destroyed if a product is fully reheated. But really, for businesses that are producing those non-ready-to-eat, ready-to-heat type ready meals, I would recommend they go to Guidance Note 46, which is our new guidance note that gives advice to food businesses around these products, and understand if there's a reasonably foreseeable risk in terms of Listeria monocytogenes – should it be determined as a hazard in their process and controlled appropriately.
And really in terms of reasonably foreseeable hazard, is there reasonable evidence to show that maybe some consumers might choose to not fully reheat those products? They may eat them warmed up for palatability purposes, which will not kill the Listeria monocytogenes. Or maybe if you have a product that has a serving suggestion of "eat hot or cold" – you know, that's a ready-to-eat product, because the consumer can eat that without heating.
What pathogens should a small food business operator be testing their products for in shelf life testing? How can we advise? Can the laboratory advise? Is there any guidance on this that we can direct the food business operator to?
Mary Lenehan, FSAI: I think it depends on what product you're making. The guidance we have is Guidance Note 18, on the Food Safety Authority of Ireland's website – you'll get that there. Tthat's the guidance note on how to approach determining shelf life for your product in general – not just specific to Listeria monocytogenes.
We also did a webinar with Safefood about 2 years ago now, and that also gives a lot of information about how to determine what pathogens to test for.
So really it's about understanding your products – what are the legal requirements, what are the national best practice guidance notes – Guidance Note 3 if it's a ready-to-eat food – and what are the pathogens that are maybe associated with that product?
So it really depends on the product, and looking at it from that view.
Are there any in-house rapid tests that are valid methods of detecting Listeria, or is it only external laboratory methods – and retaining products until results come back – for the products that can't be controlled by pH and water activity?
Mary Lenehan, FSAI: There are some rapid methods, but you'd have to risk assess whether that is suitable. You might not want to have a pathogen on your premises that you culture up out of a sample. There's a risk in terms of maybe cross-contaminating your products.
So a lot of food businesses don't have their own lab on site, or if they do, they're testing for maybe hygiene indicators, and they're sending the pathogen testing to an external lab. In terms of rapid tests, food businesses and laboratories can use those once they're shown to be equivalent to the reference method – so the ISO method that's listed in the legislation.
Catherine Coady, Sofina Foods: In the last few months, we've been approached by a number of people with these rapid methods – a pink/blue reaction within one or two hours of a swab, a surface swab within the site.
They're lovely, and they're great if you maybe had an issue, if you had a prevalence and you wanted to try and keep on top of it and just find the direction it was going.
I wouldn't say that they could be a replacement for your lab testing in any shape or form. The other side of that – rapid testing – exactly as you said – if it's equivalent, a lot of the rapid methods are not, and you may get negatives where the approved method would be a positive, because it's slightly more accurate. It's one to be careful of.
Labs can give you very good advice as well, but from a rapid method perspective, we've only ever used it as a top-up if there was an issue or something like that, not on its own.
Is the 2-day safety margin applied by many food business operators to shelf life enough? The durability studies suggest a 7-plus day assessment.
Mary Lenehan, FSAI: In terms of a margin of error, in Guidance Note 18 we would recommend food businesses maybe take back their shelf life by a day or so, considering maybe some consumers might choose not to abide by that use-by date. But it's very case-by-case as well, and up to the food business, depending as well on the shelf life.
If you have a 7-day shelf life, taking it back by 2 days is quite substantial, so you'd have to have a rationale for that. It's definitely not something that's required, but depending on the product, you may choose to do it as an additional safety measure. But I think it depends on the business.
Catherine Coady, Sofina Foods: I find that a lot of the retailers will lead on this one as well, so some require – rather than a 2-day margin – a 20%, so if your shelf life is short, it probably will land in around 1 or 2 days, but the risk is absolutely that your customer or consumer will not abide by that. Looking fine, keep going – so we would always build in, at an absolute minimum, a 20% margin of error there.
Do you use the pyramid swabbing method – i.e., swab most floors and drains?
Catherine Coady, Sofina Foods: We don't use a pyramid method per se. In our high-risk area – and it's worth noting that we're a very divided area, so each line has its own zone, for want of a better description – it's built over years of data, and we do tend to move our locations, but no, we would try and cover all drains over a period of time.
And then depending on if we're getting positives or negatives, we would increase that frequency. All drains would absolutely be covered, but I think to get a happy balance between food contact and non-food contact is just as critical as hitting a drain. And not being afraid to swab places of concern. So again – behind those slicer blades, where if the blade isn't taken off, you may not have gotten a proper hygiene clean; behind panels – that's a big one. Those panels don't come off in a general hygiene wash, and it's just – take those swabs and go everywhere, really. And then based on your results, you risk assess your frequency.
When carrying out Listeria swabbing, is it advisable to swab two or three areas using the same swab, or should every individual place be swabbed individually? We currently have a risk assessment to justify swabbing more than one area with the same swab. Is this acceptable in practice, though?
Catherine Coady, Sofina Foods: I can only speak from experience here. We have found that the labs tend not to stand over composite swabbing. So, if you are putting a number of swabs into a bag, any recent feedback I've had from labs is that they won't stand over that as being a test method that they can validate. They're not validated for a composite swab.
If you want to cover a large area – let's just say, for example, you had floor damage in multiple areas – to narrow that down, or to try and get a picture of what you're doing, yes, you could use that swab in, say, 3 or 4 different flooring areas. Your risk there, obviously, is if it's in one, you're going to cross-contaminate to another, so it depends on your risk assessment, depends on your environment.
Yes, it's possible, but it's very much case-by-case, and how you risk assess that for yourself.
Mary Lenehan, FSAI: I'd add there, that a disadvantage of maybe swabbing a number of areas – not to mention possibly cross-contaminating another area – is that when you get that result and it's positive, you have no idea which location that positive actually corresponds to. So, it's probably in one way more cost-effective, but actually in the long run, it's slowing you down in determining the root cause.
What corrective actions would you advise for the detection of Listeria innocua or Listeria welshimeri in product or the environment?
Mary Lenehan, FSAI: We would advise that food businesses would take similar corrective actions – proportional to the risk. If it's a ready-to-eat food, we wouldn't be looking for notification to the competent authority in terms of a recall or anything, because it's not pathogenic.
But it's a hygiene indicator, and Listeria monocytogenes occupies the same ecological niche as other Listeria species. So if you're finding Listeria species – particularly in your product – that means possibly Listeria monocytogenes could also cross-contaminate that product. So I would investigate it in a similar manner.
What does “good” look like for a scientific justification for a product if there is Listeria detected in a Category 1.2 group product? Externally validated pH and internally acceptable over-life preservative levels in recipe.
Mary Lenehan, FSAI: Well, I think if you're finding Listeria monocytogenes in your product, it's too late to be justifying that it won't grow beyond 100 CFU per gram. You should be doing the groundwork before that, and coming to your competent authority with your evidence.
And if the competent authority assesses your evidence and determines that actually if Listeria monocytogenes gets into that product it won't grow beyond 100 CFU per gram, the competent authority will make a note for that food business operator that the limit they can comply with is 100 CFU per gram.
But if you haven't done all that homework, and you find Listeria monocytogenes in your product, it's too late – maybe – to be doing some work after that fact to find the pH, etc. I think you need to do that work beforehand, and have that as part of your food safety management system.
Catherine Coady: Just, from the point of scientific evidence, as Mary mentioned in her slides as well – every product is different, so a ham made in one site can vary so much from a ham made in another site. So even that scientific literature that's there that may guide you into believing that your product will not support growth, I think you need to be very careful about your considerations. Every site is different, every process is different, so it would need that homework done, even if there are similar products that have scientific literature behind them. I think you'd need to be more robust than just literature on its own.
What is the best place to start in tackling compliance with Regulation 2073 for a medium-sized food business cooking their own hams and beef for retail from their own premises? They have documented their understanding of their product, have their own HACCP system and CCPs in relation to cooking their own meats, and their own sampling plan under CN3. They also they do environmental sampling and have undertaken shelf life studies, but do not undertake any 2073 testing.
Mary Lenehan, FSAI: For that type of product there are criteria that they need to comply with. Look at the legislation to determine which criteria you need to comply with. For a lot of ready-to-eat products, there's no sampling frequency in the legislation, so you base that on a risk assessment.
If you're starting from scratch to understand the requirements of 2073, I would recommend going to FSAI Guidance Note 27 – that's our guidance note on how to comply with Regulation 2073 – and there are some complementary e-learnings on that in the FSAI eLearning portal.
Would you recommend testing Listeria species in 25 grams over Listeria monocytogenes in final product?
Mary Lenehan:So 25 grams is the amount of sample that's taken for the test, whether it's in final product or at the end of manufacturing. The standard ISO actually is for Listeria species, so the lab will be testing for Listeria species, and depending on your laboratory, they might report that differently. The laboratory should always confirm, if there is Listeria species found in that product, what it is, in terms of whether it's monocytogenes or not.
Some laboratories might report it as Listeria innocua – they might give you that species information as well – or some might just report it as Listeria species.
But as I mentioned, if Listeria species is found, it's recommended to treat that as a hygiene indicator – so if you find Listeria species in your environment or in your product, it's showing you that possibly the conditions also exist that Listeria monocytogenes could be there, and you take the actions in a similar way.
Can there be too much focus on drains as a possible source of Listeria, rather than as a collection point?
Catherine Coady, Sofina Foods: Definitely, definitely. I think we tend to look down and don't look up.
And I think that's really important – that you look at everywhere on your site. Chiller units, fans, AHU units – they can be just as much a harbour point for Listeria as your drains can.
So, yes, and I think again, with that new guidance note, that gives you a much clearer picture of this whole thing around the non-food contact and food contact – even things like stop buttons, e-stops, under panels – you've got to go digging, because if it gets in, it stays in.
And drains can give you a false sense of security. If your drains are coming up negative, you can kind of walk away feeling happy, and it could be in your chiller units, or something like that – especially when you think of perhaps a product coming out of an oven into a blast chiller where it's steam and condensation that could sit in the roof or sit in the chillers and be circulated around – so we need to look up and out as much as we look down, for sure.
Are you essentially expecting scientific justification for product in Category 1.2 group, or will historical and risk-assessed environmental, raw material and barrier performance going to make a difference – including cook and other decontamination? Irrespective of all controls, does Category 1.2 need to have pH, preservative, water activity, or a maximum 4-day life?
Mary Lenehan, FSAI: I think yes. I think this whole talk has covered that. So, as part of controlling Listeria monocytogenes, having all that food safety management system in place is vital.
But also, you need to think about your products, and you need to show – if Listeria is there – how it will grow.
Has anyone any experience of using enzyme cleaning chemicals?
Catherine Coady, Sofina Foods: So yes, we would mostly use them in our slaughter plants. They are very good. Some chemical suppliers steer away from them.
I wouldn't have any experience of them specifically in controlling Listeria monocytogenes, but from a hygiene perspective, they're excellent. They are certainly an advantage because the gross cleaning and rinsing is reduced – so the enzyme cleaner, you just need to do a quick clean and apply the chemical, whereas with a standard chemical, you'd need to do a gross clean, a rinse, a chemical application. So from that perspective it can save time, but I haven't seen any literature to date on specific control for Listeria monocytogenes around it.
We use chlorine tablets in high-risk drains – should we follow suit with low-risk drains?
Catherine Coady, Sofina Foods: We use them in both. Just to be sure, and again, it's down to that understanding of which way your drains go. We do a level of low-risk Listeria swabbing as well – which would be not the norm – but again, it's for our own peace of mind. We've got that raw material coming in. Particularly, I think there was a question earlier about something that maybe has a naturally occurring level of Listeria in it – that low-risk control becomes just as important. So, yes – a low-risk swab or two, maybe not at the same frequency as high risk, but it would be a good idea.
Someone's asking how to reduce the risk of Listeria in the environment, and hence in the product, and also what is the acceptable reliable scientific justification if Listeria is detected in a Category 1.2 group? Will the historical controls and general controls in the environment – barriers, etc. – suffice as scientific justification in the event of detection in a Category 1.2 group?
Mary Lenehan, FSAI: No, is the answer really. We would be looking at the pH, the water activity, the preservatives, etc., but we'd also take into consideration your general approach to how you manage Listeria monocytogenes in that business.
So I think that information is more for the food business to determine their own risk, and a lot of that is covered in Guidance Note 45.
In addition to more sensitive methods, will there be more testing done by authorities?
Mary Lenehan, FSAI: No, they're not planning on doing more testing – so at the moment, I don't know off the top of my head how much testing is carried out, but the testing amount will remain the same. The only difference will be that it's going to switch for those Category 1.2 products to the detection method.
Can you confirm if within Chapter 1, sampling plan N equals 5 – does that apply to a food business operator or the competent authority?
Catherine Coady, Sofina Foods: The food business operator. So that's in Article 1 of Regulation 2073 – Regulation 2073 specifically applies to the food business operator, but the competent authority can also use it when assessing or verifying compliance of food businesses.
Can we send the link to the webinar that we talked about a few minutes ago?
Mairead McCann>Yes, we can – we can actually share that link as well with this webinar link, if people would like that, no problem.
Do you consider that consistently negative monitoring results over the years for Listeria are possible?
Mary Lenehan, FSAI: If you've got good control, yes, it's possible not to find Listeria monocytogenes in your product or in your environment, but I would say it's ubiquitous, and I would look a bit more closely – particularly at the environmental monitoring – if you're consistently finding negative results.
Is your environmental monitoring programme robust enough? Are you testing the places that you think it might be? And the problem with negative results is that sometimes they can give a false sense of security.
And you need to remember with Listeria monocytogenes and all bacteria, they're not distributed uniformly. So within a batch of product, you could have a low level of contamination that's sporadic throughout the batch.
That's why the more testing you do, the more likely you are to find it, both in the environment and in the product. But of course, it's a balance, because the more testing you do, the more expensive it is.
And I think you need to have a risk-based approach to your sampling programme, and again, Guidance Note 45 really talks about that.
Catherine Coady, Sofina Foods: Yeah, I think it's a little bit like – back to the focus on drains – so if you're getting a full year of absolute negative results, I do think you need to go back and look, and great if it is, but I think it's worth going back and looking at things like your floors. Is there any points where there's pooling water, or maybe a damaged floor, or a damaged flashing where water could get in behind it, causing a harbourage issue?
And again, while the drain is getting naturally cleaned and maybe you're using chlorine tablets and keeping it at bay, there may be other points throughout your process areas where you are actually finding harborage – things like your wheels on your trolley, which is in Guidance Note 45 – things like that. It's yes, the more you test, the more you find, and I think people may be slightly afraid of that – they'd rather just stick with the status quo where if they're testing these 12 drains and don't find it. I think we need to look at – it's better to find and eliminate than not knowing what's there.
What action is required if you get Listeria monocytogenes on a food contact swab?
Mary Lenehan, FSAI: You would risk assess the result and if it is possible that food has been contaminated, you need to take that into consideration. And maybe if you have some end product testing, you might have Listeria monocytogenes results also detected in that end product.
So it needs to be on a risk basis, and again, Guidance Note 45 really talks about that, and what you do in that situation.
As a cheese cutting facility for wholesale and retail, is a not-detected in 25 grams test at the end of shelf life enough to justify a 25-day shelf life? Should the whole wheel cheese producer detail the new changes in their product specs?
Mary Lenehan, FSAI: So I think for any product, you need to assess what shelf life is suitable for your product. And I think for cheese – if Listeria gets into your product, how will it grow? And if you're finding it would grow to beyond 100 CFU per gram, you're in that not detected in 25 grams territory.
In terms of the shelf life, the 25 days is made up of maybe the organoleptic profile, the hygiene profile – there are a few other things you need to take into consideration. Would that product spoil over that time?
But in terms of Listeria monocytogenes – for that business, it's really about making sure that Listeria monocytogenes doesn't get into their products. So if it gets into their products and Listeria is detected at any stage during the shelf life, it will be in non-compliance.
How can the lag phase in ComBase or other models be used to capture the WIP life of ingredients before they go into finished product, if I understood correctly during the presentation?
Catherine Coady, Sofina Foods: I actually wasn't talking about the lag phase – just the actual product life – but I do understand where they're coming from. In ComBase specifically, there are little information buttons that will give you a more detailed understanding of each of those areas.
So, for the pH, or even your starting point, where it's giving you a base log of Listeria – which you can slide back and forth and put it to zero, or you can have a starting point of maybe 3, or 8, or 10 CFUs, or whatever you want to do.
But specific to your product – if you click into those information buttons for your lag phases, that will help. But again, if you're considering worst case, you've got to go right back to the start – so your oldest raw material, your meat, if you have open dry ingredients, how long they're opened – consider it the whole way through.
Mary Lenehan, FSAI: Around lag phase specifically, we would recommend that a value of 1 is used as the default, which is the worst case scenario. Basically, lag phase is around how quickly the Listeria monocytogenes will start growing in your product, and 1 means it would start growing straight away.
If you had some justification to show that there is a different lag phase value that you could use for your product, you would need to have proof and evidence for that, but as a worst-case scenario, it's recommended to use 1 as your lag phase value.
Is excess steam an issue for some food business operators to argue that it is not condensation?
Catherine Coady, Sofina Foods: I think you'd have to prove it – which is funny really. So, yes, excess steam can be an issue – if you imagine pulling your racks or your trays out of your oven, and the steam hits – while the steam may not be condensation, it is condensing on your roof. So, anything that is on your roof that may be there – Listeria – can then cross-contaminate with that steam. Condensation control, steam control – anything like that – is absolutely critical to your Listeria control, so if you have sufficient extraction post-cook as your ovens are open, especially if you're using steam ovens, from a retailer perspective, they would consider steam and condensation one and the same. Once it hits that cold barrier, hits the roof, it is condensing.
You'd have to have a very robust assessment to prove otherwise, I think.
What are the panel's views on the use of phage technology – such as PhageGuard – as part of a cleaning and disinfection protocol?
Mary Lenehan, FSAI: Some of those products are not permitted for use in the European Union. There was one brand in particular that I know has been going through the courts about that.
But in general, the reason the European Union sees that under Regulation 852, which is the one that contains HACCP and prerequisite requirements, good hygiene and good food safety management systems are critical in producing safe food.
And that businesses shouldn't be turning to decontaminants to remove contamination at the end of manufacturing, for example. It shouldn't be there in the first place, from manufacturing under hygienic procedures.
So at the moment, those types of products are not permitted for use in the EU.
We currently accept a result of 0.97 or below for water activity in our meat products. However, I've seen on one of your slides a result of less than or equal to 0.96. So is 0.97 acceptable?
Catherine Coady, Sofina FoodsDoes the amendment apply in Northern Ireland?
Kevin Connolly, FSA: So, just in case people aren't aware – of course, the UK, which Northern Ireland is a part of, has left the EU, but following that, due to the movement of goods between Northern Ireland and the Republic of Ireland, they put in place what was called the Northern Ireland Protocol, which kept Northern Ireland aligned with certain EU rules, so that goods could move freely between the North and the South.
That caused a bit of complications politically in Northern Ireland, so then in February 2023, they reached the agreement which is called the Windsor Framework Agreement, which replaced the protocol, and in simpler terms, it was just designed to make trade smoother – so that EU law would still continue to apply in Northern Ireland – and to fix the practical and political problems without scrapping the protocol altogether. So the requirement to adopt Regulation 2073/2005 is contained within Regulation 852/2004.
Regulation 852/2004 is listed in Annex 2 of the Windsor Framework Agreement, and therefore is directly applicable in Northern Ireland. So that's where it comes to the point where Regulation 2073/2005, along with the amendment, is still applicable in Northern Ireland. Just to clear that up in case there happens to be any confusion among food business operators, either in the North or in the Republic.
Mairead McCann: And just to finish off – thank you so much again to Mary, Catherine, and Kevin for joining us all today, and all the participants. We'll be sending out a short feedback survey to you all shortly, and we'd really appreciate if you'd take a few moments to complete that.
We will have the recording up on our website shortly with some of the useful resources – the links to those that Mary shared in her slides already.
