Dear chebar,
Here is a, IMO, typical example –
As I understand, yr primary requirement is –
(1) to satisfy yr customer’s specification that foreign materials having a dimension of >2mm are not present in the product.
I will give an opinion regarding metal contamination. I assume the MD is associated with a CCP.
I assume that for detection / removal of metallic contamination at the metal detector (MD), 3 basic metallic categories are sufficient criteria for assuring compliance with requirement (1) ,ie (a) “ferrous”, (b) “non-ferrous” and © “stainless steel”. (typically as chemically detailed by MD manufacturers)
To meet requirement (1), the MD test piece for each of category (a-c) should –
(2) nominally have a maximum dimension of <= 2mm and an appropriate configuration. These are usually available from the MD manufacturer or agent.
(3) be detected and removed by the MD using a validated procedure. (signal response consistencies etc are presumably also relevant to maintenance of correct machine performance).
I included “nominally” due to this caveat regarding operational limitations of metal detectors –
The use of electronic metal detectors is complex, especially with regard to stainless steel, which is difficult to detect. The orientation of the metal object in the food affects the ability of the equipment to detect it. For example, if a detector is not properly calibrated and is set to detect a sphere 0.08 inch (2 mm) in diameter, it may fail to detect a stainless steel wire that is smaller in diameter but up to 0.9 inch (24 mm) long, depending on the orientation of the wire as it travels through the detector. Processing factors, such as ambient humidity or product acidity, may affect the conductivity of the product and create an interference signal that may mask metal inclusion unless the detector is properly calibrated. You should consider these factors when calibrating.
Regardless of the above caveat, IMEX, many processors will follow the logic of (2-3) above.
Of course, if yr MD cannot see a test piece of 2mm in a validated test procedure for any of categories (a-c), it will not be possible to fully satisfy yr customer’s specification unless an increased capabiity is available from other devices, for example magnetic separators often have higher sensitivities than a MD for ferrous contaminants, non-ferrous seem to be more problematic.
Using other detectors / separators prior to the MD, should reduce the workload on the MD. However you will need to validate that potential added risks such as due to fragments of any broken screen mesh will be detected / removed prior to / by the MD.
I hope the above is intelligible.
As far as the haccp hazard analysis is concerned, I suggest you consider the model (Canadian) example attached which seems to me rather easier to format than yr previous attachment.
You will see that the choice of “mm” settings for Critical Limit is left open since it may relate to yr local regulatory requirements / customer and also potentially depending on the target consumer category. If you have no restrictions regarding the choice, eg no defined division into safety / quality issues, etc , I daresay you can simply set the CLs as per the (a-c) test dimensions. IMEX this is typical of many haccp plans.
metal detector, haccp hazard analysis, etc.xls 81KB
56 downloads
Rgds / Charles.C
