I am attempting to construct a support system for a multi-tiered cake. I want a gap between the tiers so I was thinking about using a steel pipe up the center, then using couplers to get my separation. What type of steel should I use? Stainless, galvanized, black pipe? I see the decorators on TV use steel all the time but I unsure what type is best. Do I need to wrap the pipe with saran wrap regardless of what I use to keep the structure food safe? Is there any better method for making sure the structure is food safe?

Any input would be greatly appreciated!!!

Stainless Steel is the only steel that is gaurenteed food safe (of course you still want to clean it before using) There are grades of carbon steel that are food safe, but they're very hard to find, and i dont' think i've ever seen any in pipe form.
A lot of people use PVC, i don't like to b/c i don't think it's food safe, but some people feel comfortable using it. It is definitely cheaper than using Stainless steel!

Leily, I have no idea if this is true but I believe people say PVC is food safe because our water system runs through it. And if I understand correctly we may call the plumbing pipes PVC but I don't think they're actually PVC. It's sort of like calling all cotton swabs Q-tips. Check with your hardware store regarding PLumbing Grade pipes. I'm not saying one way or the other, just saying that there is a lot of difference in various plastics including different types of PVC so it's worth asking.

Sillywabbitz - i have heard people say that before, just personal opinion... but i understand that the inside is, but the outside has had printed ink and other things on it that i don't know if they truely come off when cleaned. I dont' know enough about how PVC pipe is actually manufacturered to know if it is or not so I havent' used it yet. Again, this is an uneducated opinion since i haven't done more research

If you are concerned about the ink on the outside of PVC you could always sand it off.

I do believe that alcohol on a cloth will remove the ink on the outside of the pipe and then you can wash it with what ever you would like. If it's safe enough for water that we drink to run thru, then I personally don't have a problem with my food touching it. JMHO.