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Alicyclobacillus: Is 49/mL a lot?/enough to detect spoilage?

food spoilage micro food micro alicyclobacillus

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Posted 29 May 2018 - 07:35 PM

Alicyclobacillus is 49/ml a lot enough to detect spoilage should there be 0 tolerance for acb to prevent spoilage or can you have a certain amount without there being an issue?

Basically my topic title says it all. Anyone have any ideas?



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Posted 29 May 2018 - 08:15 PM

this is all I could find, but it doesn't relate it directly to the amount of Alicyclobacillus to begin with



Guaiacol has been found in all 5 samples proved that it is the most important taint compound, which is similar to Pettipher’s report [28]. It has been proved that the best estimated threshold (BET) value for odour of guaiacol was around 2 ppb in apple juice [28], and similar threshold values for odour of guaiacol in apple juice were even lower in other reports

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Posted 01 June 2018 - 03:22 AM


In my experience any concentrates we purchased were to be clear of ACB.  It was not permitted.  Once ACB is in the processing system it is very difficult to remove (heat tolerant, acid tolerant).  A count of 49 CFU/ml  will only increase unless you remove(clean) the ACB from your processing environment.  You will also need to state to suppliers (if you are buying in the concentrate) that your spec for ACB is NIL.   Also you should be able to taste the guaiacol if it is present in the product.


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Posted 29 June 2018 - 09:36 AM

Alicyclobacillus is 49/ml a lot enough to detect spoilage should there be 0 tolerance for acb to prevent spoilage or can you have a certain amount without there being an issue?

Basically my topic title says it all. Anyone have any ideas?


Hopefully you've already solved your predicament, but in case it's useful should you encounter similar again...

I assume this is affecting a juice product?
We use a lot of these, and have a purchasing specification defined of <1cfu/10ml - obviously we'd all like no ACB at all, but if your supplier understands the issue then they'll reasonably assert than confirming absolute absence (0cfu/10ml) is not something that can be verified.


Not all strains of ACB produce a taint so there is a chance you could be lucky here, but it really isn't something on which you'd want to rely!

The nature / prominence of the taint will also depend on the nature of the raw material, as the availability of various substances will affect the ability of the ACB to produce the tainting compounds.


Personally if I'd found 49cfu/ml I would not release product for use or sale, and would instead be picking up with the raw material supplier to start a full investigation. If it's a clarified concentrate then there are various filtration regimes that can be applied to control this, but good practice within the general production environment is still critical to control. For cloudy concentrates and juices it's a much greater challenge, so a lot of attention should be paid to things like the washing process for incoming fruit, treatment/use of condensate water from evaporators etc.

For the material you currently have, I'd keep a few samples and see what happens to them. You may be able to get the strain typed, which could give you a better idea of whether spoilage is likely.

I'd also definitely send a sample for some further analysis - not sure what method you've used for the initial count, but my preference is definitely IFU12 for this.

Lots of labs that offer ACB analysis will also be able to do a guaiacol test with a detection kit, and this should pick it up at a lower level than the taste/smell threshold for human detection of a taint.

The external lab we use for this has actually set up a combined method for us so we request one test "package" for a sample and they'll automatically do the ACB via IFU12 and guaiacol via a detection kit. Obviously you'd hope there would be no guaiacol if there is no ACB, but I am aware of cases of people filtering to remove a known ACB problem then selling the stock back into the market...


I've (unfortunately :P ) spent quite a lot of time looking at ACB, so let me know if you need any more info and will do what I can.


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