8 replies to this topic

[Wer3005]

Please advice me on how an investigation should be carried out when the listeria monocytogenes has been found in the finished good and after the identification this has been confirmed that this is exactly the same specie as the listeria extracted from the drain in production room. Product is rte spread and the drain is below the filling and packaging line. Spread is transport in stainless container to the machine. No listeria positive on the fcs of the line.

[Charles.C]

Please advice how should be investigation carried our when the listeria monocytogenes has been found in the finished good and after the identification this has been confirmed that this is exactly the same specie as the listeria extracted from the drain in production room. Product is rte spread and the drain is below the filling and packaging line. Spread is transport in stainless container to the machine. No listeria positive on the fcs of the line.

Hi Wer,

 

Please give some details regarding -

 

(1) Product

(2) Process Stages

(3) L.monocytogenes - Regulatory Requirements at Location of Consumption.

(4) Location of drain with respect to the Process Stages

[Wer3005]

Product is the chease spread with ósme additives herbs, vegetables with 2 preservatives, pH about 4,6 Acid 0,2
Cotangens cheese is first mixed with the herbs, vegetables and preservatives on the cutter machine and mitingi also with this Device. Then is put into stainless steel container and lift upper the hopper of filling machines and fill directly to the plastic tray and covered with upper foil.
Bbd of the FG is 35 days
L.mono <100cfu at the end of shelf life is the regulatory limit.
Drain is in the same room as the cutter and filling.packaging machine.
Listeria was detected in 25 g after the production. Quantitative was < 10.
How it could get from the drain to the product?

[Charles.C]

Product is the chease spread with ósme additives herbs, vegetables with 2 preservatives, pH about 4,6 Acid 0,2
Cotangens cheese is first mixed with the herbs, vegetables and preservatives on the cutter machine and mitingi also with this Device. Then is put into stainless steel container and lift upper the hopper of filling machines and fill directly to the plastic tray and covered with upper foil.
Bbd of the FG is 35 days
L.mono <100cfu at the end of shelf life is the regulatory limit.
Drain is in the same room as the cutter and filling.packaging machine.
Listeria was detected in 25 g after the production. Quantitative was < 10.
How it could get from the drain to the product?

Hi Wer,

 

^^^(red) I guess you mean L.mono ?

 

(1) Are all the ingredients heat processed ?

(2) If (1) is No, do you monitor ingredients for L.mono ?

 

Are there Sanitation controls to prevent (Personnel) entry of Listeria, eg boot dips ?

 

Listeria/L.mono is often ubiquitous if (a)  raw materials are involved, (b) Sanitation entry controls are insufficient.

[MsMars]

Also look at your sanitation practices.  Are you using high pressure hoses near the drain that could have created aerosols that transfer to the filling machine or stainless container? Does your stainless steel container contact the floor/drain before you're lifting it up to fill the machine? 

[M D]

1- Do you test your herbs and veg or accept based on suppliers certificate? What process they undergo wash, thermal kill step?

2- If present in drain then likely on the floor, if on the floor then likely on the wheels of your container, so can anything drip from wheels into cutter when/if you lift the container?

[Wer3005]

Hi All thank you for your answer.
All raw materials for this spreads are monitored for the listeria. All batches used been clear. It looks that listeri come from environment.

[jackie.judd]

To confirm, or rule out, the drain as the source of the L. mono, there are genetic labs out there that can do DNA comparison.  You just grow each isolate in question and send them in and they run the comparison.  If you have a micro lab on site that uses an L. mono control strain for positive control work, send in growth from that one too; it can rule out lab contamination.  The lab we use is Charles River.  When you find a lab you can pick their brain about what type of DNA comparison will fit your project the best.  We had an E. coli issue a few years back; a raw ingredient kept coming in contaminated with E. coli and the supplier would not believe us or take the material back until we shared the DNA comparison results with them that showed several wild type E. coli strains present in the material and a few strains that had a tracible origin which was the same country where the supplier was harvesting the material from.  Hopefully you can find a lab that can compare your isolates.  

Edited by jackie.judd@pharmatechlabs, 01 October 2020 - 05:48 PM.

[kfromNE]

One possibility - when the drain was cleaned - water splashed up on to another surface or person who then spread it to the product.