Magnets in the Food Industry

Hi all

I am doing research on magnets used in the food industry to remove metal contaminants. I was wondering if there are any Standards or Guidelines for the magnetic strength used?
I've heard of a few companies complaining that they were marked down in audits because the magnets they used were below 3500 Gauss field strength.
Is there any grounds for this?
Any information would be helpful.

Thanks
Adelaide

I havent seen any specfic standards for gauss rating for magnets in the food industry yet. Although alot of auditors require them to be used in the food industry.

I have heard most food processing plants use 10,000 - 12,000 gauss rated magnets, unless processing flour which its recommended to keep the magnet gauss rating under 7,000.

I work with vegetables and use ceramic plate magnetic and rare earth bar magnets in the factory. We do annual strength testing on our magnets using a fish scale pull test. Manufacturers of magnets can usually tell you how much force is typical for the magnets you use and can recommend which ones you should be getting depending on your process.

Hi Adelaide,

While I can't answer your question regarding standards I can tell you that (and to confirm jpredmore) most applications I see in food production plants use magnets around 11,000 gauss - so much stronger than what you mentioned. The higher the gauss the stronger the magnet.

Also be aware that magnets, regardless of size, strength or type, will ONLY remove ferrous metals. They will NOT remove non ferrous or S/S. Talk to some magnet suppliers; but if they start telling you that they can remove NF or S/S material then move on to the next supplier.

Also, for magnets to work effectively they should be relatively close together or even overlapping and the product needs to be loose and free flowing.

Hi Adelaide,

While I can't answer your question regarding standards I can tell you that (and to confirm jpredmore) most applications I see in food production plants use magnets around 11,000 gauss - so much stronger than what you mentioned. The higher the gauss the stronger the magnet.

Also be aware that magnets, regardless of size, strength or type, will ONLY remove ferrous metals. They will NOT remove non ferrous or S/S. Talk to some magnet suppliers; but if they start telling you that they can remove NF or S/S material then move on to the next supplier.

Also, for magnets to work effectively they should be relatively close together or even overlapping and the product needs to be loose and free flowing.

Dear MDXM,

I'm sure you are not claiming that all stainless steels are totally non-magnetic ?

Regarding production line separation of (some) S/S contaminants in food processing, I have no direct experience (other than via metal detectors) however there does seem to be a substantial body of equipment manufacturers disagreeing with yr general opinion, eg -

http://www.foodonlin...ntaminants-0001

http://www.foodproce...ity_control/s-s

http://www.foodprodu...l-contamination

Rgds / Charles.C

Good Morning, 

I would like to have tour thoughts about the kind of Foreign body contamination Detection method Is more appropriate following my product characterization. 

We make Dips, antipastos, relishes and Sauces and another products in Brine or oil  it is packaged in plastic tubs from 200g to 10 kg , All is handmade process in order of that I would like to know if you guys have experiences using Magnets, I have read all the articles you posted but those apply to different products. 

We at the moment can not afford a metal detector so I am looking for options. 

 

Thanks in advance.