Safe kitchen-ready materials to drill holes in for tofu press?

I am looking to make my own tofu press to save money over a store-bought one. For those unfamiliar with the process, imagine two 9x5 loaf pans with a series of holes drilled into their bottoms for water drainage. The tofu sits between the two pans and weight is put on top to press the water out of the tofu.

I am thinking that many non-stick pans are safe to use but that once the coating is punctured, one could end up being exposed to chemicals that are not food-safe.

Are most stainless steel or aluminum baking pans just that or are they composed of multiple layers, some of which may not be food safe? What material would make sense for this? Do these materials lose their anti-rust properties if punctured like this?

Note: I have also seen designs which are two slabs of material (think cutting boards) which are squeezed together, but I want the final product to have firmed sides so this will not work well.

food-safety tofu

Best Answer

Aluminium doesn't rust, and neither does stainless steel. In both cases this is a property of the material and not a coating. While aluminium has a layer of oxide on the surface, this gets scratched in use and reforms naturally. Either of these could be used, but aluminium is much easier to drill.

Non-stick pans are usually mild steel underneath the coating. This will rust, and the rust can give an off flavour to food in quantities that aren't dangerous. Flakes of PTFE non-stick coating aren't hazardous (in fact I've seen scientific papers suggesting the same material could be used as a bulking agent in dieting) but don't look nice. I'd avoid non-stick for that reason.

Other options include:

Wood: most woods in widespread use are food-safe. My little cheese press (which I bought for tofu but also use for paneer) is some sort of softwood, probably spruce. I occasionally oil it with walnut oil.
Plastic food storage containers. Just be sure they aren't any rough bits that could end up in the food. They won't harm you in small quantities (unless somehow burnt) but won't be pleasant. Many small commercial cheese presses are made of the same plastics a food storage containers, just thicker and stronger. Food packaging probably isn't stiff enough and can be multilayered (still all food-safe plastics though).