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iggybaseball Jul24-05 01:02 PM

Materials safe for food machines
I've recently drawn up several machines that handle food. However I wanted to know if there are any materials that I should stay away from, for handling food. To clarify, I would like to go to a harware store to pick up supplies, but is it ok to run liquids or store food in pvc for example. What about when it comes to liquids. If anyone would like to suggest materials that I could use safely or that I should avoid, I would appreciate it greatly. Thanks.

brewnog Jul24-05 01:34 PM

Are you asking just about polymers?

I didn't watch it, but here is a supposed documentary about the use of PVC and other vinyls for food use. Apologies if it's useless, I couldn't be bothered to download it.

Anyway, there are concerns about the use of PVC in food applications, and in any case if your intentions are to market a product, you'll probably have to use certified food-grade plastics. Obviously, your material selection depends as much on the actual application as any safety issues, - it's pointless to use a safe plastic if it doesn't fulfil other criteria.

It should be remembered that all pure polymers themselves are non-toxic, but many additives (colourings, hardeners, stabilisers etc) added during the various manufacturing processes are.

brewnog Jul24-05 01:36 PM

I also found this excellent article at the Cooking for Engineers website.


And, also, the FDA website has a very in-depth code - Current Good Manufacturing Practice in Manufacturing, Packing or Holding Human Food, which, again, I didn't read all of!


Astronuc Jul24-05 01:45 PM

The choice of materials depends on the conditions.

Storage containers can be made of polyethylene (PE) or polyethylene terephthalate (PETE), e.g. beverage containers.

Cooking would require ceramics like Pyrex or certain whitewares, or perhaps stainless steel. In the dairy industry and food processing industry, stainless steels are used because they can be sanitized after use.

wolram Jul24-05 02:29 PM

One thing you have to sure of, is contamination, if a slither of plastic finds
its way into a food product it is virtually un detectable, nearly all mass
produced food passes through a metal detector, so any part of the machine
in contact with food should ideally be high grade s/steel.

We have audits to account for every plastic, glass item in factory, even biro
pen tops are not allowed.

FredGarvin Jul24-05 08:37 PM

Cool site Brews.

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