9 replies to this topic

[SoupsNStuff]

After searching for days, I think the answer is "do a challenge study" but just in case, i'll ask here!

 

Does anyone have any official study/regulation stating what is the lowest oxygen concentration C. bot can grow at? We are using modified atmosphere packaging MAP and have the risk of C. bot, so will use %O₂ as a control (and refrigeration of course). The product can't be changed/processed in a way that reduces this risk otherwise, sadly. 

 

We had someone say they used to use at least 4% oxygen as a CCP, but they don't remember what the regulation/justification was for it. I found a source that said at lab conditions, the limit is 1%. I found a food study that said it grew at 5% but not at 10%. Another food study said no growth at 0, 5, or 10%. Is there anything out there more definitive? 

 

Thank you :)

[Evans X.]

Greetings Soups,

 

Unfortunately there is no easy answer. As you may know from your research there are different types of Clostridium and the enzyme (superoxide dismutase) that affects the oxygen tolerance can differ due to many reasons. That is why in most cases the low oxygen concentration in the packging is accompanied by some other control measure, like heat treatment, low aw (under 0,97) or high acidity (induced or inherent), freezing etc.

Since no other processing can be done it would be a risk to go for less than the 4% that you mentioned and the lab conditions isn't what you have in practice so that you can go for the 1%.

I do have to stress out that this is just my opinion based on the facts given and that I would try to combine it with some other form of processing.

 

Regards!

[Charles.C]

After searching for days, I think the answer is "do a challenge study" but just in case, i'll ask here!

 

Does anyone have any official study/regulation stating what is the lowest oxygen concentration C. bot can grow at? We are using modified atmosphere packaging MAP and have the risk of C. bot, so will use %O₂ as a control (and refrigeration of course). The product can't be changed/processed in a way that reduces this risk otherwise, sadly. 

 

We had someone say they used to use at least 4% oxygen as a CCP, but they don't remember what the regulation/justification was for it. I found a source that said at lab conditions, the limit is 1%. I found a food study that said it grew at 5% but not at 10%. Another food study said no growth at 0, 5, or 10%. Is there anything out there more definitive? 

 

Thank you :)

Hi SNS,

 

I think you may be missing the point of implementing vacuum/MAP packing although it may depend on yr product/process which you have unfortunately omitted.

 

eg - What is the purpose in removing/replacing oxygen ? How low % must oxygen be so as to achieve yr desired product (eg increased shelf life) effect ?

[SoupsNStuff]

Hi SNS,

 

I think you may be missing the point of implementing vacuum/MAP packing although it may depend on yr product/process which you have unfortunately omitted.

 

eg - What is the purpose in removing/replacing oxygen ? How low % must oxygen be so as to achieve yr desired product (eg increased shelf life) effect ?

 

Sorry about that! The purpose is to lessen spoilage organism growth/shelf life. The product is cooked to 165F and chilled to 38F, stored refrigerated, MAP packed in a tray. pH not low enough, salt not high enough, and water activity not low enough to be a control. 

 

"How low % must oxygen be so as to achieve yr desired product (eg increased shelf life) effect ?"

 

Yes, that's the question. I was wondering if people had experience (and thus records/justification) for a certain level of O2 that gave them their shelf life without having the risk of C. bot due to too low O2. I definitely could have provided more detail in my op so I apologize. 

[Charles.C]

Sorry about that! The purpose is to lessen spoilage organism growth/shelf life. The product is cooked to 165F and chilled to 38F, stored refrigerated, MAP packed in a tray. pH not low enough, salt not high enough, and water activity not low enough to be a control. 

 

"How low % must oxygen be so as to achieve yr desired product (eg increased shelf life) effect ?"

 

Yes, that's the question. I was wondering if people had experience (and thus records/justification) for a certain level of O2 that gave them their shelf life without having the risk of C. bot due to too low O2. I definitely could have provided more detail in my op so I apologize. 

Hi SNS,

 

No problem. Thks clarification.

Not my area but I recall previous threads posting links to Tables of recommended MAP mixtures. I remember the MAP mix  varies with specific product type which is so far unmentioned. Meat ?

[Scampi]

https://www.chilledf...Final-Jul18.pdf

 

https://www.scienced...phere-packaging

 

https://www.cfs.gov...._fsf_46_01.html

 

one or all may include the info you seek 

 

Happy researching!

[sqflady]

You would definitely want to do a challenge study specific to your product.  The properties of your product may impact the results.

[SoupsNStuff]

Thanks everyone! I did end up getting that 4% reference, but it isn't enough for us to put all our faith on. So challenge study it is!

[SoupsNStuff]

I've attached the file for future reference :) 

Attached Files

•  O2 amount to inhibit Cl botulinum (002).pdf   459.57KB   21 downloads

Edited by SoupsNStuff, 07 October 2021 - 07:04 PM.

[Charles.C]

I've attached the file for future reference :) 

Hi SNS,

 

Yr precise Product/intended MAP mix is unspecified but, as you imply, the document in Post 9 (1929) may not be relevant.

 

JFI can compare to the links in Post 6 and, say, these articles -

 

 C.botulinum_in_VP_and_MAP foods,2006.pdf   1.27MB   17 downloads

 C.botulinum in MAP chilled fish fillets,2007.pdf   165.11KB   13 downloads

 

From a C.botulinum Safety POV, I suggest to implement the UK/US recommended control criteria.