Transcript: Managing Listeria in ready-to-eat food production

• Print

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.