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elbochra

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Posted 31 December 2014 - 01:19 PM

Hello,

I work in a wheat mill and we have just implemented a HACCPapproch.

This approach noted one CCP is the magnet and screen line-end process

Thank you for helping me in the definition of a suitable frequency of inspection and take into consideration two things

  • Difficulty in opening équipement
  • The flour is directly loaded and shipped right after bag filling.

note : we haven't a metal detector

 

best regards



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Posted 31 December 2014 - 01:42 PM

We don't have our magnets as CCPs but that is because we have a metal detector at the end of the bagged line process.

 

One issue with having your magnet as a CCP is that it won't take out non-ferrous metal so you can't say that it is removing all metal.  Also you have to have a critical limit which can be hard to define for a magnet.  Furthermore do you have metal screen material in your sifters?  Are those ferrous or nonferrous screens?  If they are nonferrous the screen material may break apart and get into your product... please don't ask how I may or may not have knowledge of this issue.  Though we have found that even "nonferrous stainless steel" can be attracted by a magnet just not strongly.  Another issue is that your magnet will not detect if something falls into the product from your bagging line itself.

 

If your magnet is truly going to be a CCP it does have to be able to be opened, inspected, and cleaned at a determined frequency.  Our magnets are CPs (or oPRPs in FSSC same thing different name) because of the issues listed above.  However all of our magnets are pretty easy to open and inspect.  We check those after every milled load of product.

 

Our flour may sit around for a short period of time in our warehouse (really just a large alcove) for a day or two before shipping but there are times we have to move them out the same day. 

 

You should inspect the magnet at least once at the start of a load and once at the end of the load.  That way if there is an issue it's only on that one load.  I don't know how long your bagging runs are ours is about 2 to 2 1/2 hours.  You could shut down bagging operations long enough to inspect it, which in a close easy to open and inspect magnet shouldn't take more than 5 minutes, and then be able to inspect it every hour or so.  

 

The frequency of your CCP inspection is really determined by how much risk you want to put into your product.  If you determine your product is at risk and you bagged out an entire load of flour then you have scrap that load and start over.


Edited by Mr. Incognito, 31 December 2014 - 01:43 PM.

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elbochra

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Posted 31 December 2014 - 05:39 PM

thank you for your reactivity

but our magnet and screen  end of line  aren’t  easy to open and our bagging runs are about 1 to 1 1/2 hours.



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Posted 31 December 2014 - 05:49 PM

Elbochra,

 

The longer you take between checking your CCP the more product you put at risk if you find a problem.  For this reason a CCP should be checked as frequently as possible.  If you find out 6 hours after the previous check that your CCP has been violated by not being performed correctly or there is an issue then you have to recall 6 hours worth of product that has already shipped.  

 

My suggestion is to get a metal detector for the end of the bagging line or getting a new magnet that is easier to open and inspect between loads.  Again a magnet will not protect you from all metal contamination though in milling neither will a metal detector.  Small screen material can pass through a metal detector without being found which is why having a robust multilevel metal protection is important.


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Charles.C

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Posted 31 December 2014 - 08:17 PM

Dear elbochra,

 

Yr haccp plan should be based on a hazard analysis. The frequency of monitoring of a CCP is likely to be related to yr validated, acceptable level of contamination / critical limit / operational findings / post 4.

 

Significant hazards take priority over machine/human limitations. :smile:

 

If you are interested in studying the various posted haccp plans for various types of grain milling on this forum, could try searching for flour, corn, wheat, grain, mill.

 

I have previously summarized most of the older postings somewhere, will add to this post if i can find it.

 

(added) - just for example, try -

 

http://www.ifsqn.com...lls/#entry62122

 

 

Rgds / Charles.C


Kind Regards,

 

Charles.C


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Posted 02 January 2015 - 06:39 AM

Dear Elbochra,

 

I have added a link to previous post with 2 examples of haccp plans.

The second attachment offers some possible insight into yr OP query, particularly when read in conjunction with posts #2 and #4.

 

Rgds / Charles.C


Kind Regards,

 

Charles.C


swanswal

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Posted 06 January 2015 - 11:51 PM

Hi elbochra. 

 

If your company decides the magnet is a CCP, then so be it.  Some do, some don't.  Most companies I see have the magnets as part of a PRP, using Metal detectors and X Rays as CCP's.

 

The only thing I would add to the posts so far is that the Critical Limits for the magnet in my view should be based on it's minimum strength and loading limit (eg no less than 8,000 gauss and no more than 50% of face covered), not on the output of the magnet (eg 2 metal pieces).  This situation is similar to thermal processing, where the Critical Limits for the thermal process is based on the process itself (time and temp), and not the output of such a process (viable microorganisms per gram).  This has been mentioned before in this Forum.

 

Outputs of metal removal processes are validated and verified to ensure effectiveness (eg metal size/location in product flow trials for validation, customer complaint feedback for verification).  If the magnet system is properly validated, the finding of metal on it should cause no concern, as long as it has not been overwhelmed with metal.  Your checking frequency would be such that under normal circumstances, the strength and loading limits were not exceeded.

 

Hope this helps.



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Posted 07 January 2015 - 02:48 PM

Dear swanswal,

 

Thks for input. Interesting.

 

I have no direct experience with magnets but as you noted, magnets designated as CCPs have been previously discussed here (within various formats) but, AFAI could see, with no decisive conclusion. :smile:  For example  –

 

http://www.ifsqn.com...magnets-as-ccp/

http://www.ifsqn.com...magnet-as-a-cp/

 

I suggest that from the POV of the magnet’s operation, the hazard is  failure to remove (ferrous?) metal considered to be hazardous so that the critical limit(s) for it’s operation presumably demand (a) the specification of “hazardous” metal and (b) the specification of measurable parameters which ensure the (complete) removal of metal contaminants defined by (a).

[sort of borrowed from current CFIA-MD hazard intro  –

Attached File  CFIA, MD-haccp detail.png   294.15KB   6 downloads

 

Assuming that (a) is answerable (eg regulatory, customer, machine), the haccp query on yr premise seems to be whether a magnet can validatably, consistently, achieve (a) when maintained within certain machine parameters (stable?) and  which are (I presume) readily monitorable plus (hopefully) readily adjustable in the event of a failure of a critical limit.

 

Can it? Evidence ?

 

So far I have not seen any support data either way but I suspect the MD industry believes (hopes) that the answer is negative. And possibly the source of my attachment in earlier post. :smile:

 

Rgds / Charles.C

 

PS - Kraft also have some partially relevant opinions on this topic  -

Attached File  haccp extraneous material.pdf   48.34KB   290 downloads


Kind Regards,

 

Charles.C


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Posted 07 January 2015 - 05:48 PM

We have magnets at the bagging station which are checked at the start of every shift.  We also have magnets throughout the process, but only the ones at the packout stations are our CCP.  We hold the product and investigate with a metal detector if anything 1mm or larger is found.  So we would only need to hold the previous shift's product, which is not a huge amount.

 

For some further information:

 

All of our equipment is ferrous metal.  Our screens for our sifters are also ferrous.  Our only risk factors are metal fragments in the product, since our food is not ready to eat.

 

We are not a flour mill, but there are some similarities.  We make food grade cellulose fibers and powder, so our raw materials are highly purified cellulose pulp sheets.  We can state that the only source of metal fragments in the product would be from the machinery so it all would be ferrous.

 

We are considering adding a metal detector at the end and monitor the bags as they exit the bag press, but that brings up the issue of what happens when metal is detected.  If we put a metal detector on the conveyer of the bag press, we can't have a automatic system to remove the bags from the conveyer, they would have to be sequestered manually.  So we need to work that out when we want to move to GFSI certification.  Any suggestions there for us?

 

We fill one bag at a time, and though people don't touch the product, it is individually filled and weighed.  So this is not a hugely automated process, it will be easy to identify the bag that failed the metal detector and remove it.  If there is a question, we can run the bag back through the detector to verify.

 

Insights :welcome:

 

Martha


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Posted 07 January 2015 - 06:48 PM

Dear Widra,

 

Thks for input.

 

I deduce that yr critical limit for the magnet is a positive detection of metal particle > 1mm.

 

How do you set-up/validate  that yr magnet is reliably detecting metal particles of >= X mm ? ( X = 1mm?)

(I'm guessing that the magnet is paired with a sieve (somehow))

 

Rgds / Charles.C


Kind Regards,

 

Charles.C


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fgjuadi

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Posted 07 January 2015 - 07:00 PM

We have a magnet / screen as a CP and a metal detector as a CCP.  

When I worked at a flour mill the metal detector was the CCP, the magents were...not CPs.  They were something we checked every couple hours and recorded, and they were part of foreign object control, but not critical, as they would pick up quite a bit of rust dust. 


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MWidra

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Posted 07 January 2015 - 07:05 PM

Dear Widra,

 

Thks for input.

 

I deduce that yr critical limit for the magnet is a positive detection of metal particle > 1mm.

 

How do you set-up/validate  that yr magnet is reliably detecting metal particles of >= X mm ? ( X = 1mm?)

 

Rgds / Charles.C

We consider the magnet is not a detection system, but a removal system.  Like a kill step, it removes a hazard.  In that way, it does control a risk.

 

Your question is well taken, and we are working on a comprehensive validation documentation.  We perform sieve tests of our product, so many pieces of metal that were in the product would be found in that testing.  And we do not see metal fragments in our sieve testing, which has a final size sieve of 200 µ.  So over time, we would see items if they were not being removed.  We have considered that testing as the validation of the magnets' effectiveness.

 

We also have identical magnets upstream from the final magnet, and they occasionally find and remove small pieces of metal.  Since they are not at the end of the process, they are not a CCP, but they can and do remove 1mm pieces of metal.

 

We have begun strength testing of our magnets for documentation.  This testing is in the beginning stages, and I need to implement this in a more organized fashion.  It was being performed in an informal fashion by Maintenance, so I'm going to set up a more well-documented program for that.

 

All good points, and we're working on a total scheme to make the validation into a neat package.

 

Martha


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Posted 07 January 2015 - 09:11 PM

Dear MWidra,

 

Thks for comments. 200microns is I guess 0.2mm. That is quite fine.

 

I am guessing that the magnet function is typically not fine-tuned as per an MD, ie it is set to grab anything / everything over a much wider range (0-10mm?), the choice presumably based on gauss level/orientation. IMO this could still work from a validation POV but equally remains to be quantitated (if possible) with respect to particle size. As I understand, the process you describe is based on the finished product unit which is presumably more complicated to interpret than direct magnet output, but maybe not depending on the flowchart. Either way, yr method offers an opportunity to use the Codex validation via pilot study approach. :smile:   

 

I have just read another haccp analysis of wheat milling which concludes that all of the magnets used within the main process are PRPs (eg categorizable as part of "cleaning" activities) and also for the magnets/MD at the packaging step. The logic at the packaging step is that all the sieving/sifting already carried out means that the possibility of metal occurring of a size relevant to FS is remote (ie presumably as per your 200micron). Net result is that the MD is only preventing metal contaminants which would cause quality issues. (Not sure if auditors would readily buy this).

 

In contrast, the grain website below gives a diametrically opposed end-stage opinion, ie CCPs, but without any risk-related data other than noting that metal contaminants below 7mm are anyway considered not a risk ! –

http://www.world-gra...plan.aspx?cck=1

 

Looks like a stand-off. :smile:

 

Rgds / Charles.C

 

PS - I deduce (as per OP) that the magnet is typically combined with a sieve, this may in practice be a more representative control measure unit :dunno: .


Kind Regards,

 

Charles.C


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Posted 07 January 2015 - 09:27 PM

We have magnets at the bagging station which are checked at the start of every shift.  We also have magnets throughout the process, but only the ones at the packout stations are our CCP.  We hold the product and investigate with a metal detector if anything 1mm or larger is found.  So we would only need to hold the previous shift's product, which is not a huge amount.

 

 

Thanks Martha and to all responding to this magnet thread.  It can be a challenging topic to get your head around, but it really need not be.

 

Please let me put a challenge to your comment on a Critical Limit of a piece of metal 1mm or larger you hold stock....

 

Imagine for a moment you run an orange juice factory making juice for babies.  Your hazard is pips.  You install a 2mm screen that removes pips.  What is the critical limit?  Is it if you catch a pip?

 

Kind regards to all......



Charles.C

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Posted 07 January 2015 - 09:44 PM

Dear Swanswal,

 

Define / validate a hazardous pip ?

 

Rgds / Charles.C


Kind Regards,

 

Charles.C


swanswal

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Posted 07 January 2015 - 10:38 PM

Thanks Charles.  Always enjoy these discussions...

 

In this example, I would define a hazardous pip as any pip (seed) greater than 2cm diameter (assume spherical).  Big pips I agree but is just as an example and we have big oranges down here in Australia!   Validation comes from (in this example) this USDA position...

 

http://www.fsis.usda...gnMaterials.pdf

 

In this example, we tested a sieve with round 2cm apertures against 100 orange pips 2cm or greater and all 100 were retained on the sieve....

 

cheers


Edited by swanswal, 07 January 2015 - 10:44 PM.


Charles.C

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Posted 08 January 2015 - 09:45 AM

Dear swanswal,

 

There are IMO some potential haccp traps in yr hypothesized saga (even after accepting jumbo Australian babies),  notably  –

(1) Defining a haccp hazard.

(problems with vintage validations I will defer).

 

Regarding (1) and the chosen topic, for a not too dissimilar but nearer real-time case, can have a look at this brief thread –

http://www.ifsqn.com...size-of-stones/

 

Of course, an American baby would probably sue.

 

Attached File  post-225-1248421529.jpg   40.85KB   2 downloads

 

In some ways, it seems to me this general metallic topic for officialdom is an extension of zero-tolerance pathogens, can’t live with 'em, can’t live without 'em. Unfortunately haccp is risk-based so a collision is almost inevitable. I guess that’s why the USA love “adulteration”.

 

And I still don’t know how you meaningfully validate a magnet with respect to size. :smile:

 

Rgds / Charles.C


Kind Regards,

 

Charles.C


elbochra

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Posted 08 January 2015 - 11:37 AM

HELLO

A big  thank you for everyone for taking a part and being involved in this very productive discussion.

the solution that we have adopted is to minimize the frequency of control and put the product on hold after correct sieve and magnet  inspection  until  installation metal detector

best regards





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