Food Processing Machine - Food Safe Aluminum

Sounds similar to a pizza press.

Did you try USDA or FDA about an approved material selection.

Remember its not always what's approved, its what material is approved for your areas regulation requirements AND can endure the environment the best.

Choosing the best compromises to satisfy both area is the difficult part.

Rather than considering a specific aluminum alloy, I would look at the various coatings that could be applied to the surfaces that would contact the product. There are a wide array of surface treatments available to provide chemical inertness, corrosion resistance, and non-stick properties.

By the way, 1100 series Al, while providing excellent corrosion resistance and good thermal conductivity, is miserable to machine.

You have to be careful with coatings, they have to be approved for food contact.

And that is a laughable joke.

In the dairy industry (USDA-3A), Teflon coating is approved, the down side is Teflon wears/chips off.... guess where that Teflon goes? Bon Appétit.

One other thing, this is being heated, you need the thermal properties to effectively transfer the heat. Aluminum is a good choice for this.

FDA has most aluminum alloys on the GRAS list. Though as I understand it they have never been tested.

How your going to heat the plate may make difference. If your going to cast the heat element into the plate. I don't know how well 1100 cast.

Also are these plates he has coated to make them non-stick.

These are heated with small elements on either side of the plates. And I don't believe they are cast.

The FDA did not have an Approved List of aluminum alloys for use in casting. I did an appreciable amount of castings used in the pharmaceutical and food industries. The information that I obtained from Alcoa and others was that 356, 214, 43 and 713 were good corrosion resistant alloys and used for castings in those applications. Avoid use of copper bearing alloys. They said to avoid 2xxx and 7xxx alloys due to the copper content. The 5xxx series was acceptable until you got to a magnesium content in excess of 3% and should be limited to 150 F max temp. That would preclude the use of 535 (Al-Mag) and 220 alloy. Didn't use 214 since it had over 3% mag and was lousy to machine. Use of Teflon coatings should be limited to less than 400 F as I remember. The use of 6063 and 6061 was acceptable. Note that the 4 digit alloys are not for casting but are mill products.